Effectiveness of Novel Drug Delivery System using Curcumin in Alzheimer's Disease.

Alzheimer's disease (AD) is a form of brain degeneration that gradually impairs a person's memory and cognitive skills, eventually making it harder for them to perform everyday activities. Its pathophysiology has been attributed to the deposition of amyloid ß (Aß), neurofibrillary tangles (NFT), and α-synuclein (A-s) in some cases. Presently, 4 drugs have been approved for the treatment. They are Donepezil, Rivastigmine, Galantamine and Memantine. The first three are acetylcholinesterase inhibitors, while memantine is an NMDA receptor antagonist. Even though these medications are successful in treating mild to moderate Alzheimer's disease, they have not been able to reverse the disease or even slow its progression completely. Hence, natural products are gaining more popularity due to the advantage of the multitarget intervention effect. The most investigated spice, Curcuma longa's bioactive component, curcumin, has demonstrated anti-amyloid, anti-NFT, and anti-Lewy body properties and substantial antiinflammatory, antioxidant, and antiapoptotic properties. However, its proven neuroprotective activity is hampered by many factors, such as poor water solubility and bioavailability. Therefore, many novel formulations have been designed to improve its bioavailability with methods such as 1) Micellar Solubilization, 2) Cyclodextrin Complexation, 3) Crystal Modification, and 4) Particle Size Reduction, etc. The current chapter aims to summarize various novel formulations of curcumin and their effectiveness in treating AD.

Rodent models for diabetes.

Diabetes mellitus (DM) is associated with many health complications and is potentially a morbid condition. As prevalence increases at an alarming rate around the world, research into new antidiabetic compounds with different mechanisms is the top priority. Therefore, the preclinical experimental induction of DM is imperative for advancing knowledge, understanding pathogenesis, and developing new drugs. Efforts have been made to examine recent literature on the various induction methods of Type I and Type II DM. The review summarizes the different in vivo models of DM induced by chemical, surgical, and genetic (immunological) manipulations and the use of pathogens such as viruses. For good preclinical assessment, the animal model must exhibit face, predictive, and construct validity. Among all reported models, chemically induced DM with streptozotocin was found to be the most preferred model. However, the purpose of the research and the outcomes to be achieved should be taken into account. This review was aimed at bringing together models, benefits, limitations, species, and strains. It will help the researcher to understand the pathophysiology of DM and to choose appropriate animal models.

Recent Advances in the Endogenous Brain Renin-Angiotensin System and Drugs Acting on It.

The RAS (renin-angiotensin system) is the part of the endocrine system that plays a prime role in the control of essential hypertension. Since the discovery of brain RAS in the seventies, continuous efforts have been put by the scientific committee to explore it more. The brain has shown the presence of various components of brain RAS such as angiotensinogen (AGT), converting enzymes, angiotensin (Ang), and specific receptors (ATR). AGT acts as the precursor molecule for Ang peptides-I, II, III, and IV-while the enzymes such as prorenin, ACE, and aminopeptidases A and N synthesize it. AT1, AT2, AT4, and mitochondrial assembly receptor (MasR) are found to be plentiful in the brain. The brain RAS system exhibits pleiotropic properties such as neuroprotection and cognition along with regulation of blood pressure, CVS homeostasis, thirst and salt appetite, stress, depression, alcohol addiction, and pain modulation. The molecules acting through RAS predominantly ARBs and ACEI are found to be effective in various ongoing and completed clinical trials related to cognition, memory, Alzheimer's disease (AD), and pain. The review summarizes the recent advances in the brain RAS system highlighting its significance in pathophysiology and treatment of the central nervous system-related disorders.

Corrigendum to “Phytochemical analysis and antifertility potential of Cynodon dactylon in female Wistar rats: A herbal approach towards contraception” Chin Herb Med 12 (2020) 281–288 (Chinese Herbal Medicines (2020) 12(3) (281–288), (S1674638420300496), (10.1016/j.chmed.2020.06.001)) / 中草药·英文版

When this paper was first published the following ethical statement was omitted in error: Experimental conditions and procedures involving animals were approved by Institutional Animal Ethics Committee (IAEC), H.K.E.S. MTR Institute of Pharmaceutical Sciences, and carried out in accordance with laboratory animal use guidelines of IAEC (Permit Number: HKECOP/IAEC/91/2017-19). The authors would like to apologise for any inconvenience caused. DOI of original article: https://doi.org/10.1016/j.chmed.2020.06.001

Prophylactic effects of asiaticoside-based standardized extract of Centella asiatica (L.) Urban leaves on experimental migraine: Involvement of 5HT1A/1B receptors / 中国天然药物

The present study aimed at evaluation of prophylactic efficacy and possible mechanisms of asiaticoside (AS) based standardized extract of Centella asiatica (L.) Urban leaves (INDCA) in animal models of migraine. The effects of oral and intranasal (i.n.) pretreatment of INDCA (acute and 7-days subacute) were evaluated against nitroglycerine (NTG, 10 mg·kg(-1), i.p.) and bradykinin (BK, 10 μg, intra-arterial) induced hyperalgesia in rats. Tail flick latencies (from 0 to 240 min) post-NTG treatment and the number of vocalizations post-BK treatment were recorded as a measure of hyperalgesia. Separate groups of rats for negative (Normal) and positive (sumatriptan, 42 mg·kg(-1), s.c.) controls were included. The interaction of INDCA with selective 5-HT1A, 5-HT1B, and 5-HT1D receptor antagonists (NAN-190, Isamoltane hemifumarate, and BRL-15572 respectively) against NTG-induced hyperalgesia was also evaluated. Acute and sub-acute pre-treatment of INDCA [10 and 30 mg·kg(-1) (oral) and 100 μg/rat (i.n.) showed significant anti-nociception activity, and reversal of the NTG-induced hyperalgesia and brain 5-HT concentration decline. Oral pre-treatment with INDCA (30 mg·kg(-1), 7 d) showed significant reduction in the number of vocalization. The anti-nociceptive effects of INDCA were blocked by 5-HT1A and 5-HT1B but not 5-HT1D receptor antagonists. In conclusion, INDCA demonstrated promising anti-nociceptive effects in animal models of migraine, probably through 5-HT1A/1B medicated action.

Effect of aqueous extract of Solanum xanthocarpum Schrad. & Wendl. on postmenopausal syndrome in ovariectomized rats / 中西医结合学报

Solanum xanthocarpum Schrad. & Wendl. (Solanaceae) is present in many Ayurveda compound formulations including Chavanaprasha and Dasamoolarishta. The whole plant is used in conditions such as inflammation, constipation and promoting conception in females. In the present study, we carried out different tests to evaluate the effect of aqueous extract of Solanum xanthocarpum (SXE) in postmenopausal syndrome.

Effect of aqueous extract of Solanum xanthocarpum Schrad. & Wendl. on postmenopausal syndrome in ovariectomized rats / 中西医结合学报

<p><b>OBJECTIVE</b>Solanum xanthocarpum Schrad. & Wendl. (Solanaceae) is present in many Ayurveda compound formulations including Chavanaprasha and Dasamoolarishta. The whole plant is used in conditions such as inflammation, constipation and promoting conception in females. In the present study, we carried out different tests to evaluate the effect of aqueous extract of Solanum xanthocarpum (SXE) in postmenopausal syndrome.</p><p><b>METHODS</b>The study was carried out in bilaterally ovariectomized one-month-old Wistar rats (40-50 g). Bilaterally ovariectomized (OVX) Wistar rats were divided into four groups (n=6) receiving different treatments, consisting of a vehicle (distilled water), aqueous extract of Solanum xanthocarpum at two different doses (200 and 400 mg/kg) administered orally daily for 90 d and standard drug β estradiol at a dose of 1 mg/kg administered subcutaneously biweekly for 90 d. Estrogenic activity was assessed by vaginal cornification, sexual behavior, serum estradiol and uterine weight to body weight ratio. Antiosteoporotic activity was assessed on the basis of biomechanical and biochemical parameters followed by histopathological studies, and antidepressant activity was assessed by forced swim test.</p><p><b>RESULTS</b>SXE showed presence of steroids. At the dose of 200 mg/kg, it significantly improved all the parameters of sexual behavior (P<0.01), caused vaginal cornification, and increased serum estradiol and uterine weight (P<0.01). It also significantly improved all the parameters of bone strength as well as depression (P<0.01). Histopathology of bones confirmed the above findings.</p><p><b>CONCLUSION</b>The study indicated that SXE may provide an effective treatment in the prevention of postmenopausal symptoms.</p>