Dendrimers are nanosized, symmetrical molecules in which a small atom or group of atoms is surrounded by the symmetric branches known as dendrons. The structure of dendrimers possesses the greatest impact on their physical and chemical properties. They grow outwards from the core‐shell which further reacts with monomers having one reactive or two dormant molecules. Dendrimers’ unique characteristics such as hyperbranching, well‐defined spherical structure, and high compatibility with the biological systems are responsible for their wide range of applications including medical and biomedical areas. Particularly, the dendrimers’ three‐dimensional structure can incorporate a wide variety of drugs to form biologically active drug conjugates. In this review, we focus on the synthesis, mechanism of drug encapsulations in dendrimers, and their wide applications in drug delivery.

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder related to age, characterized by the cerebral deposition of fibrils, which are made from the amyloid-β (Aβ), a peptide of 40–42 amino acids. The conversion of Aβ into neurotoxic oligomeric, fibrillar, and protofibrillar assemblies is supposed to be the main pathological event in AD. After Aβ accumulation, the clinical symptoms fall out predominantly due to the deficient brain clearance of the peptide. For several years, researchers have attempted to decline the Aβ monomer, oligomer, and aggregate levels, as well as plaques, employing agents that facilitate the reduction of Aβ and antagonize Aβ aggregation, or raise Aβ clearance from brain. Unluckily, broad clinical trials with mild to moderate AD participants have shown that these approaches were unsuccessful. Several clinical trials are running involving patients whose disease is at an early stage, but the preliminary outcomes are not clinically impressive. Many studies have been conducted against oligomers of Aβ which are the utmost neurotoxic molecular species. Trials with monoclonal antibodies directed against Aβ oligomers have exhibited exciting findings. Nevertheless, Aβ oligomers maintain equivalent states in both monomeric and aggregation forms; so, previously administered drugs that precisely decrease Aβ monomer or Aβ plaques ought to have displayed valuable clinical benefits. In this article, Aβ-based therapeutic strategies are discussed and several promising new ways to fight against AD are appraised.

: In the brain, acetylcholine (ACh) is regarded as one of the major neurotransmitters. During the advancement of Alzheimer's disease (AD) cholinergic deficits occur and this can lead to extensive cognitive dysfunction and decline. Acetylcholinesterase (AChE) remains a highly feasible target for the symptomatic improvement of AD. Acetylcholinesterase (AChE) remains a highly viable target for the symptomatic improvement in AD because cholinergic deficit is a consistent and early finding in AD. The treatment approach of inhibiting peripheral AChE for myasthenia gravis had effectively proven that AChE inhibition was a reachable therapeutic target. Subsequently tacrine, donepezil, rivastigmine, and galantamine were developed and approved for the symptomatic treatment of AD. Since then, multiple cholinesterase inhibitors (ChEIs) have been continued to be developed. These include newer ChEIs, naturally derived ChEIs, hybrids, and synthetic analogues. In this paper, we summarize the different types of ChEIs which are under development and their respective mechanisms of actions.

Euphorbia hirta linn., is a species of Euphorbiaceae family. They are known as asthma plant, barokhervi. The plant E. hirta is famous for its medicinal importance among the tribal population. It is a common practice to use the whole to heal wounds. Several pharmacological properties including antiseptic, anti-inflammatory, antidibetic, antispasmodic, antibacterial, antiviral, antifungal, anticonvulsant, nootropic, antifertility and aphrodisiac properties have already been reported for this plant. The aim of present work was to evaluate the wound healing property in diabetic animals by oral and topical administration of ethanolic extract of E. hirta whole plant. The ethanolic extract of E. hirta was subjected to determine the total phenolic content and total flavonoid content using galic acid and quercetin, respectively as standard. A single injection of alloxan monohydrate (120 mg/kg, i.p.) prepared in normal saline was administered to produce diabetes in rats, after overnight fasting. For analyzing the rate of contraction of wound, excision wounds sized 4.90cm2 and of 2 mm depth were used. Oral (100, 200 and 400 mg/kg/day; p.o.) and topical treatment with the extract (5% and 10% ointment 50 mg/kg/day) and standard (5% povidone iodine ointment 50 mg/kg/day) was started on the day of induction of wound and continued up to 16 days. The means of wound area measurement between groups at different time intervals were compared using ANOVA and Dunnet’s test. The diabetic wound healing mechanism was studied by measuring the plasma level of glucose, malondialdehyde (MDA) and nitric oxide (NO) in both control and treated groups. For the confirmation of activity, histopathology of the wounds tissues from excision wound model was performed. Phytochemical investigations showed the presence of various phytoconstituents (carbohydrates, saponins, alkaloids, glycosides, steroids, flavonoids, tannins). In the ethanolic extract of E. hirta the total phenol content was 285 ± 3.22 mg/g whereas the total flavonoid content was 118.46 ± 1.85 mg/g. In the present study, E. hirta caused significant wound closer both orally (35.92%, 44.69% and 61.42% at the doses of 100, 200 and 400, respectively) and topically (32.86% and 36.32% at the doses of 5% and 10%) treated groups as compared to diabetic control. However, the orally treated groups showed more significant effect than the topically treated groups. Moreover, oral administration of E. hirta ethanolic extract significantly reduced the blood glucose levels in diabetic wound rats (p < 0.01) on day 8 and day 16 as compared to the diabetic wound control (p < 0.01). On the other hand, topical application of E. hirta did not influence the blood glucose levels in diabetic rats (p > 0.05). It also demonstrated a significant decrease in the plasma levels of lipid malondialdehyde and nitric oxide. The results of biochemical parameters were further supported by the histopathological changes of different organs (liver, pancrease, kidney, heart and skin from wound area) which were evidenced through a decrease in inflammatory cell infiltration. The present study demonstrates that E. hirta whole plant extract promotes healing of wounds more significantly as compared to diabetic control rats, where healing is otherwise delayed.

The medicinal plants signify a massive basin of potential phytoconstituents that could be valuable as a substitute to allopathic drugs or considered as an analogue in drug development. Phyllanthus niruri L. (Euphorbiaceae) is generally used in traditional medicine to treat ulcer and inflammation. In this project we investigated the methanolic extract of leaves of Phyllanthus niruri for anti-inflammatory and anti-ulcer activity. The anti-inflammatory activity of methanol extract of Phyllanthus niruri leaves was evaluated at the doses of 100, 200 and 400 mg/kg, p.o. while using ibuprofen (20 mg/kg, p.o) as the standard drug. The animals used were Swiss albino rats. Inflammation was induced by injecting 0.1 ml carrageenan (1% w/v) into the left hind paw. Paw tissues from the different groups were examined for inflammatory cell infiltration. On the other hand, antiulcer activity of methanolic extract of P. niruri leaves at the doses of 100, 200 and 400 mg/kg, p.o. were examined against ethanol-acid induced gastric mucosal injury in the Swiss albino rats - keeping omeprazole (20 mg/kg, p.o.) as reference. The rats were dissected and the stomachs were macroscopically examined to identify hemorrhagic lesions in the glandular mucosa. P. niruri significantly (p < 0.01) decreased carrageenan-induced paw edema; it exhibited a reduction of 46.80%, 55.32% and 69.14% at doses of 100, 200 and 400 mg/kg, respectively. These findings were further supported by the histological study. The methanolic extract also disclosed good protective effect against ethanol-acid induced gastric mucosal injury in the rats. Administration of the extract’s doses (100, 200 and 400 mg/kg) demonstrated a significant (p < 0.01) reduction in the ethanol- acid induced gastric erosion in all the experimental groups when compared to the control. The methanolic extract at the higher dose (400 mg/kg) resulted in better inhibition of ethanol-acid induced gastric ulcer as compare to omeprazole (20 mg/kg). Histological studies of the gastric wall revealed that toxic control rats revealed mucosal degeneration, ulceration and migration of numerous inflammatory cells throughout the section. On the other hand, MEPN treatment groups showed significant regeneration of mucosal layer and significantly prevented the formation of hemorrhage and edema. The investigation suggests that methanolic extract of P. niruri leaf possess anti-inflammatory activity and promotes ulcer protection as ascertained by regeneration of mucosal layer and substantial prevention of the formation of hemorrhage and edema.