Diarylheotanoid from Alnus hirsuta improves glucose metabolism via insulin signal transduction in human hepatocarcinoma (HepG2) cells

Natural Products as Potential Lead Compounds for Drug Discovery Against SARS-CoV-2

For the past 2 years, the coronavirus responsible for the COVID-19 infection has become a world pandemic, ruining the lives and economies of several nations in the world. This has scaled up research on the virus and the resulting infection with the goal of developing new vaccines and therapies. Natural products are known to be a rich source of lead compounds for drug discovery, including against infectious diseases caused by microbes (viruses, bacteria and fungi). In this review article, we conducted a literature survey aimed at identifying natural products with inhibitory concentrations against the coronaviruses or their target proteins, which lie below 10 µM. This led to the identification of 42 compounds belonging to the alkaloid, flavonoid, terpenoid, phenolic, xanthone and saponin classes. The cut off concentration of 10 µM was to limit the study to the most potent chemical entities, which could be developed into therapies against the viral infection to make a contribution towards limiting the spread of the disease.

Diarylheptanoids as nutraceutical: A review

Phenolic compounds are naturally occurring compounds present ubiquitously in plants. They have potential health benefits and substantiate evidence for their nutraceutical applications. Diarylheptanoids are part of the broad class of plant phenolics with structurally divergent compounds. They have been used in traditional medicines and homemade remedies to treat various ailments, as organoleptic additives in foods, and also for aesthetic purposes. With their potential therapeutic and organoleptic characteristics, diarylhepatanoids can be rightly termed as nutraceuticals. This review summarizes the wide range of pharmacological activities of diarylhepatanoids and nutraceutical formulations, with relevance to human health.

In vitro anti-diabetic effect of flavonoids and pheophytins from Allophylus cominia Sw. on the glucose uptake assays by HepG2, L6, 3T3-L1 and fat accumulation in 3T3-L1 adipocytes

BACKGROUND AND PURPOSE

Based on ethno-botanical information collected from diabetic patients in Cuba and firstly reported inhibition of PTP1B and DPPIV enzymes activities, Allophylus cominia (A. cominia) was identified as possible source of new drugs that could be used for the treatment of type 2 diabetes mellitus (T2-DM).

EXPERIMENTAL APPROACH

in this study, the activity of the characterised extracts from A. cominia was tested on the glucose uptake using HepG2 and L6 cells, 3T3-L1 fibroblasts and adipocytes as well as their effect on the fat accumulation using 3T3-L1 adipocytes.

KEY RESULTS

on 2-NBDG glucose uptake assay using HepG2 and L6 cells, extracts from A. cominia enhanced insulin activity by increasing glucose uptake. On HepG2 cells Insulin EC₅₀ of 93 ± 21nM decreased to 13 ± 2nM in the presence of the flavonoids mixture from A.cominia. In L6 cells, insulin also produced a concentration-dependent increase with an EC₅₀ of 28.6 ± 0.7nM; EC₅₀ decreased to 0.08 ± 0.02nM and 5 ± 0.9nM in the presence of 100μg/ml of flavonoids and pheophytins mixtures, respectively. In 3T3-L1 fibroblasts, insulin had an EC₅₀ of >1000nM that decreased to 38 ± 4nM in the presence of the flavonoids extract. However, in adipocytes, insulin produced a significant concentration-dependent increase and an EC₅₀ of 30 ± 8nM was a further confirmation of the insulin responsiveness of the adipocytes to the insulin. At 100µg/ml, flavonoids and pheophytins extracts decreased fat accumulation in 3T3-L1 adipocytes by two folds in comparison to the control differentiated cells (p < 0.05). The crude extract of A. cominia did not show any enhancement of 2-NBDG uptake by 3T3-L1 adipocytes in the presence or absence of 100nM insulin. In addition, in fully differentiated adipocytes, both extracts produced significant decrease in lipid droplets in the cells and no lipid accumulation were seen after withdrawal of the extracts from the cell growth medium. However, there was no effect of both extracts on total protein concentration in cells as well as on Glut-4 transporters.

CONCLUSIONS AND IMPLICATIONS

the pharmacological effects of the extracts from A. cominia observed in experimental diabetic models were shown in this study. A. cominia is potentially a new candidate for the treatment and management of T2-DM.

The Genus Alnus, A Comprehensive Outline of Its Chemical Constituents and Biological Activities

The genus Alnus (Betulaceae) is comprised of more than 40 species. Many species of this genus have a long history of use in folk medicines. Phytochemical investigations have revealed the presence of diarylheptanoids, polyphenols, flavonoids, terpenoids, steroids and other compounds. Diarylheptanoids, natural products with a 1,7-diphenylheptane structural skeleton, are the dominant constituents in the genus, whose anticancer effect has been brought into focus. Pure compounds and crude extracts from the genus exhibit a wide spectrum of pharmacological activities both in vitro and in vivo. This paper compiles 273 naturally occurring compounds from the genus Alnus along with their structures and pharmacological activities, as reported in 138 references.

The antidiabetic effects of an herbal formula composed of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng in the streptozotocin-induced diabetic rats

A folk prescription consisting of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng has been used in the treatment of diabetes mellitus. The aim of the present investigation was to evaluate the antidiabetic effects of the herb formula extract (HFE) composed of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng in the streptozotocin (STZ)-induced diabetic rats. The HFE was mixed in the food supply of the healthy and STZ-induced diabetic male Sprague-Dawley rats, and its effects on the body weight, water and food intake, hyperglycemia, hypolipidemic and islet structure were studied. The treatment of the rats with STZ for 6 weeks resulted in marasmus, polydipsia, polyphagia, hyperglycemia and hypoinsulinemia. In addition, the diabetic rats showed an apparent decrease in the insulin immunoreactivity and the number of β-cells in the pancreas. The addition of the HFE to the rats' food supply significantly lowered the serum glucose and the serum triglycerides level and preserved the normal histological appearance of the pancreatic islets. These results indicate that the HEF have a strong antidiabetic potential along with the significant hypoglycemic and hypolipidemic effects, which may be applicable in the pharmaceutical industry.