Towards A New Frontier in Alzheimer’s Disease Treatment: Promising Medicinal Plants and Bioactive Compounds

Abstract

A neurological disorder that deteriorates with age, Alzheimer's disease (AD) is typified by significant cognitive impairment, memory loss, and aberrant behaviour. There is currently no cure, despite much investigation, and the only relief offered by existing medications is symptomatic. The creation of efficient therapeutic approaches is essential given the rising prevalence of AD worldwide. Recent advances in our knowledge of the pathophysiology of AD have led to the discovery of novel therapy targets, increasing the likelihood of more direct involvement in the disease process. Clinical research is currently being conducted on a number of Ayurvedic medicinal herbs that are gaining attention as potential sources of bioactive compounds. These herbs may help control the symptoms and course of AD because they include substances including lignans, flavonoids, tannins, and polyphenols that have a variety of pharmacological actions, such as anti-inflammatory, anti-amyloidogenic, and antioxidant properties. Despite these encouraging results, there are only five licensed medication therapies for AD at this time, and they mostly target symptom management rather than slowing the disease's progression. Recent research emphasizes the importance of early diagnosis using state of the art techniques including cerebrospinal fluid biomarkers and amyloid PET scans. This may facilitate the implementation of disease-modifying therapies during the preclinical stages of AD, when neurodegeneration is not yet clinically noticeable. Even though new clinical trials like the ones looking into aducanumab show promising results, care must be taken when interpreting them. Even while disease-modifying medications might someday postpone the onset of dementia, much more study needs to be done before they are generally accessible. This review emphasizes the promise of both conventional pharmacological and Ayurvedic approaches in offering innovative treatment choices for AD, highlighting the necessity of further research to identify and evaluate effective disease-modifying therapies.

Keywords

Introduction

Fig: 1.1 Symptoms of AD

A: secretase enzyme inhibitors; B: NMDA receptor modulators, such memantine; C: immunotherapy, which consists of vaccines and monoclonal antibodies; D: antitau therapy; E: Anticholinesterase inhibitors, such donepezil; F: NSAIDs and other anti-inflammatory drugs.  APP stands for amyloid precursor protein, NFTs for neurofibrillary tangles, NSAIDs for non-steroidal anti-inflammatory drugs, and NMDA for N-methyldisparate.

• Tau thesis:

Tau is a protein found in neurons that normally stabilizes microtubules in the cell's cytoskeleton. In Alzheimer's disease, tau becomes hyperphosphorylated, leading to its accumulation into neurofibrillary tangles (NFTs) inside neurons. These abnormal tau aggregates disrupt normal cellular functions by interfering with other proteins. Research suggests that hyperphosphorylation of tau may be triggered by amyloid-beta (Aβ) accumulation, occurring downstream in the disease process.

• The cholinergic thesis:

In the 1970s, the first major finding in the research was the identification of a cholinergic deficiency in the brainpower of advertisement patients, which was caused by impairments in the enzyme choline acetyltransferase. As a result, the cholinergic thesis of advertising was developed, and the significance of acetylcholine in memory and comprehension was recognized. It also triggered sweats to increase cholinergic exertion medically.  Cholinergic decrease is a late feature of the neurodegenerative cascade.  By inhibiting the cholinesterase enzyme, which hydrolyzes acetyl choline at the synaptic split, cholinesterase obstacles enhance cholinergic transmission.

• Excitotoxicity:

Excitotoxicity, which is defined as excessive exposure to the neurotransmitter glutamate or overstimulation of its N-methyl-D-aspartate (NMDA) receptor, is mostly responsible for the slow death of neurons in advertisements.  This process is thought to have an impact on the devilish amount of calcium that enters cells due to the loss of cholinergic neurons.

• Neuroinflammation:

Neuroinflammation, driven by glial cell activation, plays a key role in the development of Alzheimer's disease (AD). The brain was once considered immune-privileged due to the blood-brain barrier and its limited immune response. However, this view has changed, as both amyloid plaques and neurofibrillary tangles are now recognized as potential triggers for immune activation. Targeting neuroinflammation has become a major focus in AD treatment. In the 1990s, studies suggested anti-inflammatory drugs might protect against AD. While naproxen may offer some preventive benefit in healthy older adults, clinical trials and meta-analyses show that NSAIDs, aspirin, and steroids provide no benefit once symptoms have started. This suggests that the therapeutic window may occur early in the disease process, before symptoms appear.¹⁹

DIAGNOSIS OF AD:

For Alzheimer's disease to be efficiently treated as soon as feasible, an early and precise diagnosis is crucial. These herbal medicines, when paired with regular brain exercises, should be started as soon as possible after diagnosis to improve the likelihood of leading a normal and healthy life. The following tests are part of a comprehensive evaluation that can accurately diagnose Alzheimer's disease:

• A thorough medical and mental health history
• Neurological examination
• Laboratory testing to rule out vitamin deficiencies, anemia, and other illnesses
• Mental status evaluation to assess the patient's memory and thought processes
• Conversations with family members or caregivers.²⁰

Assessment of Mental Status Alzheimer's complaint existent tests:

• The Mental Status Examination (MSE) is a vital individual test for mania like Alzheimer's.²¹
• The Mini- Cog test, which takes roughly three beats to give, is constantly used in exigency apartments for cases who feel to have madness, similar as Alzheimer's complaint.²²
• Urinalysis Urine test if Alzheimer's complaint or another kind of madness is suspected, your croaker may perform routine urine analysis as one of the tests. Urine tests, or urinalysis, check for anomalies. Urinalysis can identify a variety of ails or affections, similar as severe renal complaint, whose symptoms can act mania.²³
• MCI, or mild cognitive impairment Indeed if they will only be suffering from minor cognitive impairment, people may sometimes sweat the launch of madness. Visual suggestions for Diagnosing Dementia There are several important visual pointers that someone might have madness, including Alzheimer's complaint. Particular hygiene, vesture, and appearance can all decline. Although they're precious, visual cues only reveal one hand of mortal geste and donation that could help with opinion.²⁴
• Test for Lumbar Perforation Despite being occasional in madness examinations, lumbar perforations can identify unusual diseases that can act madness symptoms.²⁵
• The Mini Mental State Examination (MMSE) is most frequently used to evaluate memory problems and support the implicit belief that someone is insane.²⁰
• Alzheimer's complaint can be diagnosed with the help of the electroencephalogram (EEG). The brain swells that are recorded on the EEG show a broad and symmetrical decelerating in those who have the condition. ²⁶

ALZHEIMER'S DISEASE PREVENTION AND THE PART OF BIOACTIVE MIXES:

Scientists are looking at the action of plant bioactive mixes after disquisition revealed that some salutary factors reduce the trouble of advertisement. Natural bioactive mixes are allowed of as shops'" secondary metabolites." In this regard, it has been demonstrated that a variety of mixes isolated from a variety of shops, including roots, rhizomes, leaves, and seeds, enhance cholinergic signalling and help the conformation of mischievous sanctum.²⁷ Antioxidant-rich foods lessen oxidative stress in the brain. Because herb derived compounds exhibit a wide range of pharmacological benefits, scientists are consequently keen in employing them to create combinations that can treat a number of ailments. Results indicated that certain naturally being bioactive substances are sufficient for the treatment of advertisement. Details on these chemicals are handed below.²⁸

Alkaloids

A large number of recognized flowering plant families include alkaloids, a class of nitrogenous chemicals. Some species, like the Solanaceae, Papaveraceae, Amaryllidaceae, and Ranunculaceae, have a large number of alkaloids, while many species have a small amount.²⁹ Additionally, fungi like ergot, amphibians like the poison dart frog, and rodents like the new world beaver create alkaloids.   It's interesting to note that galantamine and rivastigmine, two AChEIs that have received FDA approval, are alkaloids.³⁰

1. Galantamine

An allosteric modulator of nicotinic acetylcholine receptors (nAChRs), galantamine is an isoquinoline alkaloid that is found in Leucojum aestivum, Galanthus caucasicus, and Galanthus woronowii. Experimenters created mongrel motes that target NMDARs, particularly the NR2B subunit, by joining galantamine and memantine with different linkers. Some displayed substantial neuroprotective action against NMDA- convinced toxin, with micromolar affinity and nanomolar IC ?? values; one medicine had an IC ?? of 0.28 nM. likewise, galantamine- indole  mongrels were docked to rhAChE and  worked  as binary-  point impediments, with indole targeting the  supplemental anionic  point( papas) and galantamine binding the catalytic active  point( CAS). Three displayed strong inhibition of pang, with IC ?? s ranging from 0.011 to 0.015 μM.³¹

2. Huperzines

Huperzia serrata, or club moss, is a traditional Chinese medicinal condiment that contains two crucial lycopodium alkaloids huperzine A and huperzine B. These composites are used to treat colourful conditions including fever, muscle strain, schizophrenia, edema, and cognitive confusion. Huperzine A is a potent and reversible asset of acetyl cholinesterase pang and butyrylcholinesterase (BuChE), with IC ?? values of 0.82 NM and 74.43 nM, independently. Huperzine B, however less potent (IC ?? =  14.3 μ M), also reversibly inhibits pang. These natural alkaloids serve as structural leads in the development of further effective pang impediments (AChEIs). Experimenters have designed new composites grounded on huperzine A's carbobicyclic core and tacrine’s 4- aminoquinoline motif, incorporating colourful substituents to enhance energy. Also, heterodimers combining huperzine a derivations with donepezil suchlike units (similar as dimethoxyindanone) connected via methylene linkers have shown pledge as pang impediments, potentially useful in treating Alzheimer’s complaint. new imine  derivations of huperzine A featuring substituted  sweet rings  parade Nano molar range pang inhibition,  backed by π – π  mounding  relations with  crucial amino acid  remainders in the pang active  point. Also, new huperzine B analogs have been synthesized, where a flexible chain links the huperzine half to an sweet ring, enabling commerce with the supplemental anionic point (papas) of pang. Likewise, mongrel motes combining rhein (a hydroxyanthraquinone) with huprine Y have been developed. These  composites interact with both the catalytic active  point( CAS) and papas of pang,  furnishing binary-  point inhibition via π – π  mounding and hydrophobic  relations, enhancing  remedial  eventuality.³²

3. Berberine

A benzylisoquinoline alkaloid derived from Phellodendron amurense and Berberis species, exhibits strong anti-inflammatory, anti-cancer, antibacterial, cardioprotective, and neuroprotective effects. It selectively inhibits AChE over BuChE and antagonizes NMDA receptors (particularly NR1), while reducing voltage-dependent potassium currents contributing to neuroprotection. In Alzheimer's disease, berberine enhances cholinergic activity and improves cognition. Novel triazole-berberine compounds showed strong docking with TcAChE, and thiophenyl-berberine hybrids modified by sulfur substitution inhibited Aβ aggregation and displayed enhanced antioxidant activity.^{33, 34}

4. Aporphine

The aporphine alkaloids found in Menispermum dauricum, including oxoisoaporphine and oxoaporphine, exhibit significant bioactivities, including blocking telomerase and cholinesterase, reducing the aggregation of Aβ, and offering antioxidant advantages. Because of π-π mounding with the Trp279 residue of stitch, oxoisoaporphines are more effective stitch obstacles than oxoaporphines.  Ammonium or amine groups improved stitch selectivity and water solubility.  Strong Aβ aggregation inhibition was demonstrated by oxoisoaporphine-tacrine hybrids connected by aminoalkyl tethers (35.5 – 85.8 at 10 μM). Furthermore, nuciferine derivatives such 1, 2-dihydroxyaporphine and dehydronuciferine showed stitch inhibition with IC ?? values of 28 and 25 μ g /mL.^{35, 36}

Polyphenols, including flavonoids

Fruits and vegetables, particularly those belonging to the Polygonaceae, Rutaceae, and Leguminosae families, contain flavonoids, which are polyphenols with potent neuroprotective, antioxidant, and anti-inflammatory qualities.  The quantity and location of hydroxyl groups determine their capacity to scavenge free radicals.  Flavonoids are structurally categorized as flavones, flavonols, isoflavones, neoflavonoids, flavanones, catechins, and chalcones based on the location of the B ring and the state of oxidation of the C ring.  Flavonoids can pass the blood-brain barrier and show promise in lowering neuroinflammation and promoting cognitive health in models of Alzheimer's disease, despite their sometimes low bioavailability.³⁷

1. Flavones

Many medicinal plants contain flavones, which have a number of health advantages. Flavones and their derivatives exhibit biological features such as neuroprotection, anti-inflammatory, and antioxidant actions, and they also inhibit advanced glycation products (AGEs). These substances may also show promise as preventative and therapeutic agents for AD.³⁷

2. Isoflavones

Isoflavonoids can be derived from microorganisms and found in leguminous plants like soybeans. When microorganisms and plants interact, they act as building blocks for the creation of phytoalexin.  These drugs inhibit MAO-B and AChE.³⁸

3. Flavanones

Hesperetin and colored flavanones are significant flavonoid groups.  Flavanones are abundant in citrus fruits, such as oranges, grapefruit, tangerines, failures, and limes.  Citrus fruits scavenge free revolutionaries and have anti-inflammatory and blood-lipid-lowering properties.  Flavanones are therefore becoming frequently utilized in multitarget-directed ligand (MTDL) products.^{39, 40}

4. Chalcones

The abecedarian flavonoid shell structure's ring C is appropriate for chalcones, another noteworthy class of open chain flavonoids. Chalcones are present in several foods, such as ladies' fingers and tomatoes.   Chalcones and their derivatives have caught the attention of researchers as possible anti-Alzheimer's medications due to their varied biological effects.^{41, 42}

5. Neoflavonoids

The hydroxyl group at position 2 that is present in flavonoids is absent from neoflavonoids, which are naturally occurring polyphenolic chemicals with a 4-phenylchromen backbone.  Numerous plants contain coumarin, a common neoflavonoid with a number of therapeutic uses. Molecular modeling suggests that coumarin inhibits Aβ aggregation by interacting with the anionic site of acetylcholinesterase (AChE). A tacrine coumarin hybrid was developed by linking the two moieties with a piperazine-based alkyl Spacer. This hybrid exhibited moderate EqBuChE inhibition (0.234 μM), significant anti-aggregation action, and strong EeAChE inhibition (0.092 μM). In multi-target-directed ligands (MTDLs), coumarin derivatives substituted at positions 6 and 7 with alkyl chains ending in diethylamino groups exhibit nanomolar AChE inhibition, neuroprotection, and around 60% inhibition of Aβ42 aggregation, suggesting disease-modifying potential.^{43, 44}

Curcumin

Long utilized in traditional medicine, curcumin is a natural substance with potent neuroprotective, anti-inflammatory, and antioxidant qualities.  In rats treated with Aβ, it reduces oxidative stress, inflammation, and cognitive impairments by efficiently blocking Aβ aggregation and fibril formation.  Through metal chelation, lipid peroxidation reduction, β-secretase suppression, and improved HSP (heat shock protein) synthesis—a molecular chaperone that inhibits protein aggregation curcumin affects the formation of amyloid plaque. It also blocks tau protein β-sheet formation, a key factor in tau-related neurodegeneration. Curcumin suppresses proinflammatory cytokines, reduces Aβ accumulation in endothelial and neuronal cells, and protects against quinolinic acid-induced neurotoxicity. In AD models like Tg2576 mice, it demonstrates broad systemic effects, making it a promising, low-cost, pleiotropic therapy for Alzheimer's disease. ^{45, 46, 47, 48}

Terpenes

Parthenolide and artemisinin are examples of sesquiterpene lactones, which are terpenoids made from isoprene units and have anti-inflammatory and neuroprotective qualities.  Parthenolide, which is present in Tanacetum parthenium, has the potential to treat neuroinflammation in diseases such as intracerebral hemorrhage because it enhances cognition and inhibits NF-κB, which lowers pro-inflammatory cytokines (TNF-α, IL-6).  Alzheimer's disease (AD) may be treated with artemisinin, which is derived from Artemisia annua and also passes the blood-brain barrier. Carnosic acid and carnosol, diterpenes from Rosmarinus officinalis, exhibit similar brain-permeable neuroprotective effects. Ginkgolides, from Ginkgo biloba, show mixed results in AD clinical trials, though one RCT reported improved cognitive and functional outcomes.^{49, 50, 51}

Resveratrol

Red wine, almonds, and grapes all contain resveratrol, a nonflavonoid with antioxidant, neuroprotective, and anti-inflammatory qualities.  To  cover neurons, it increases sirtuin  exertion, decreases Aβ peptide accumulation, and promotes nonamyloidogenic APP processing. Resveratrol is a promising treatment for Alzheimer's  complaint (announcement) since it also reduces ROS, raises GSH and Ca2, alters AMPK and nitric oxide signaling, inhibits acetylcholinesterase (pang), and binds to Aβ pillars to help remove them.^{52, 53}

MEDICINAL PLANTS FOR THE TREATMENT OF ALZHEIMER'S DISEASE:

Herbal treatments and reciprocal curatives have been used to treat neurological issues since ancient times. Numerous herbal drugs have been used worldwide to treat neurodegenerative ails. Herbal drugs are getting more and more well- liked due to its perceived cost, safety, and effectiveness. Actually, substantiation and support for the use of herbal treatments for memory related problems have only lately started to come from scientific studies. Then are many exemplifications of shops that have remedial uses.

1. Ginkgo biloba:

Because of its neuroprotective, antiapoptotic, and antioxidant properties, ginkgo biloba is frequently used to treat Alzheimer's disease (AD) and cognitive impairment. Its active compounds include terpenoids (ginkgolides A–C, bilobalide) and flavonoids (quercetin, kaempferol, isorhamnetin). These act through free radical scavenging, anti-amyloid, and anti-inflammatory pathways. GB reduces ROS, apoptosis, and mitochondrial dysfunction, while enhancing glutathione peroxidase, SOD, and cerebral oxygen flow ultimately improving cognition in AD.⁵⁴

2. Salvia officinalis:

Because Salvia species, particularly Salvia officinalis, are rich in polyphenols, flavonoids, terpenoids, and essential oils, they have great potential for treating Alzheimer's disease and other brain illnesses. Important substances with cholinergic-enhancing, anti-inflammatory, anti-amyloid, and antioxidant properties include tanshinones, carnosic acid, and rosmarinic acid. Salvia supports memory retention by activating muscarinic and nicotinic receptors, modulating acetylcholine levels, and protecting neurons from oxidative stress. Its compounds also influence cognition, mood, and neuroprotection, making it a promising natural therapy for brain health.⁵⁵

3. Rosmarinus officinalis :

Traditional medicine has long utilized rosemary (Rosmarinus officinalis), which possesses potent antioxidant, anti-inflammatory, and neuroprotective properties.  Its active ingredients, which include ursolic acid, rosmarinic acid, eugenol, and other naturally occurring COX-2 inhibitors, inhibit AChE and BChE enzymes linked to memory loss in Alzheimer's disease (AD), lower NF-κB and TNF-α, and fight β-amyloid toxicity. These actions help improve cognition, reduce neuroinflammation, and protect against neurodegeneration, making rosemary a promising natural agent for managing AD symptoms.⁵⁶

4. ?????? monnieri:

Triterpenoids, alkaloids, saponins, and important neuroprotective substances like bacosides A and B are all abundant in the classic nootropic plant bacopa monnieri. These enhance neuronal repair, restore synaptic function, support kinase activity, and improve nerve impulse transmission. With strong antioxidant and neuroprotective effects, BM shows great potential in managing Alzheimer’s disease, particularly by protecting and regenerating brain cells.⁵⁴

5. Curcuma longa:

Turmeric (Curcuma longa) contains curcumin, a potent anti-inflammatory, antioxidant, and anti-amyloidogenic polyphenol with strong neuroprotective effects. Curcumin and related curcuminoids bind to amyloid-β, reduce oxidative stress, lower proinflammatory cytokines, and improve cognitive function making turmeric a promising natural agent for Alzheimer’s disease. Notably, long-term low doses are more effective than high doses in reducing AD risk and symptoms.⁵⁴

6. Melissa officinalis:

Lemon balm (Melissa officinalis) contains phenolic acids, flavonoids, rosmarinic acid, and triterpenes like ursolic and oleanolic acid, offering neuroprotective, antioxidant, and anti-cholinesterase effects. It interacts with nicotinic and muscarinic receptors, inhibits acetylcholinesterase, and helps regulate the cholinergic system, improving cognition and reducing agitation in Alzheimer’s patients. Its compounds also help destabilize β-amyloid, making lemon balm a promising natural remedy for Alzheimer’s disease.⁵⁴

7. Convolvulus pluricaulis:

Shankhpushpi (Convolvulus pluricaulis) is a traditional nootropic condiment known for enhancing memory and cognition. Rich in triterpenoids, flavonoids, and steroids, it exerts anti-inflammatory, antioxidant, and neuroprotective goods. It reduces stress hormones like cortisol, improves literacy and memory (especially in growing smarts), and modulates the cholinergic system by adding acetylcholinesterase exertion in the hippocampus. Its multitarget action supports its use in managing cognitive decline and Alzheimer’s complaint.⁵⁴

8. Tinospora cordifolia:

Guduchi, a herb from the Menispermaceae family, is renowned in Ayurveda for boosting memory and learning. It benefits both healthy individuals and those with cognitive issues, partly due to its choline content, which supports immune function and acetylcholine production key for memory. Recent studies confirm that a 200 mg/kg aqueous root extract significantly improves logical memory and verbal learning.⁵⁴

9. Centella asiatica:

Gotu kola (Centella asiatica), from the Apiaceae family, is rich in saponins and known for its cognitive, calming, and blood-purifying benefits. Widely used in Ayurveda, its aqueous extracts help rejuvenate brain cells, ease tension, and aid insomnia. It may also protect against Alzheimer’s by inhibiting κ-amyloid formation. Studies on Wistar rats show that 250 mg/kg of fresh leaf extract significantly improves learning and memory.⁵⁴

10. Glycyrrhiza glabra:

Licorice (Glycyrrhiza glabra), a perennial herb with medicinal roots, is rich in bioactive compounds like glycyrrhizin, glabridin, flavonoids, and saponins. Traditionally used for various ailments, it also shows promise in treating neurological disorders such as Alzheimer’s, dementia, and cognitive impairment. Its antioxidant and anti-inflammatory properties help protect brain cells, improve memory, and reduce neuropathic pain. Key compounds like glycyrrhizin and glycyrrhetinic acid exhibit neuroprotective effects by countering amyloid-β toxicity. Despite its promise, more research is required to evaluate its long-term safety.⁵⁴

11. Galanthus nivalis:

Galanthus nivalis (snowdrops), a bulbous plant in the Amaryllidaceae family, is rich in alkaloids like galantamine, which has proven effective against Alzheimer’s disease. Historically used for neurological conditions, its phytochemicals—terpenoids, flavonoids, and alkaloids—offer acetylcholinesterase inhibition, anti-inflammatory, and neuroprotective effects. Galantamine enhances cognitive function by blocking acetylcholinesterase and activating nicotinic receptors, which protects neurons from β-amyloid toxicity. In vitro studies show its methanolic extract strongly inhibits acetylcholinesterase, highlighting GN's potential as a therapeutic for Alzheimer’s.⁵⁴

12. Huperzia serrata:

Huperzia serrata, a member of the Lycopodiaceae family, contains compounds like huperzine A, which are known for their neuroprotective effects. Traditionally used for various ailments, it has demonstrated anticonvulsant, anti-inflammatory, anti-Alzheimer, and anti-schizophrenia properties. Huperzine A, extracted from the plant, inhibits acetylcholinesterase, improving cognitive function in Alzheimer's models. Research on standardized extracts, like NSP01, reveals that compounds such as ferulic acid, caffeic acid, and huperzine a work synergistically to protect neurons and enhance neuronal survival. These findings suggest H. serrata as a promising neuroprotective agent for Alzheimer's treatment.⁵⁴

13. Clitoria ternatea:

Clitoria ternatea, also known as "butterfly pea," is a tropical herb from the Fabaceae family, widely used in Ayurveda for its cognitive-enhancing properties. Its root extract, rich in compounds like ternatins, delphinidin, and kaempferol, improves memory and learning by boosting acetylcholine levels in the hippocampus and promoting dendritic growth in the amygdala. Studies show it enhances spatial memory in rats and protects against cognitive decline in Alzheimer's models. C. ternatea also supports neurogenesis and offers neuroprotective effects, though further research is needed to confirm its safety and efficacy in humans. ⁵⁷

14. Desmodium gangeticum:

The imperishable plant Desmodium gangeticum, also known as salpani in Hindi, is widely grown in India and has long been utilized for its antiemetic, digestive, and anti-inflammatory properties.  Alkaloids, flavones, and glycosides are some of its chemical constituents.  Research indicates that its waterless extract improves mice's memory and guards against scopolamine-induced amnesia and cognitive decline associated with age.  Additionally, D. gangeticum shows anti-inflammatory, antioxidant, and acetylcholinesterase inhibitory properties, which may indicate that it can be used to treat Alzheimer's.  However, more research is needed to verify its efficacy and safety in people.⁵⁷

15. Moringa oleifera:

Native to India, this multipurpose tree is well- known for its high oleic acid content and antibacterial  parcels. Vitamins A and C, polyphenols, and other bioactive substances are abundant in its leaves. M. oleifera possesses nootropic, anti-inflammatory, anti-diabetic, and anti-cancer parcels. According to preclinical exploration, it improves cognitive performance by re-establishing dopamine, serotonin, and norepinephrine situations and stabilizing brain monoamines. By lowering Aβ pathology, it also aids in precluding differences linked to Alzheimer's. These results point to Moringa oleifera as a implicit neuroprotective and cognitive enhancer.⁵⁷

FUTURE PROSPECTIVE

Investigating ethno medicinal plants for the treatment of Alzheimer's disease (AD) has promise, but there are still significant information gaps that need to be addressed.   Future research should focus on identifying the active components, standardizing dosage and extracts, and employing clinical trials to verify efficacy and safety. A deeper comprehension of processes, pharmacokinetics, and medication interactions is essential, as are toxicology profiles.  Furthermore, ethical practices in bioprospecting will be ensured by taking into account genetic characteristics and honoring cultural contexts.  This strategy might improve the utility of conventional therapy and result in advances in the treatment of AD.

CONCLUSION

Ethnomedical plants hold a lot of promise for treating AD because they contain bioactive compounds that target key AD pathways. These plants affect oxidative stress, metal dysregulation, inflammation, tau protein phosphorylation, amyloid-beta aggregation, and cholinergic deficits.   Some extracts have the potential to reduce oxidative stress, alter tau phosphorylation, correct metal imbalances, and prevent the formation of amyloid plaque.   Cholinergic and anti-inflammatory substances found in these plants may also aid with neuroinflammation and neurotransmitter deficits. Although encouraging, it is still difficult to turn these discoveries into drugs that work, and more study—including clinical trials—is required to confirm their safety and effectiveness.  Medicinal plants provide a feasible substitute for AD treatment with fewer side effects, enhancing the quality of life for individuals impacted by the disease, especially considering the high expenses and hazards associated with conventional medical research.

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