A protective role of arecoline hydrobromide in experimentally induced male diabetic rats

Novel Phytochemical Constituents and their Potential to Manage Diabetes

BACKGROUND

Diabetes is a chronic disease affecting a large population worldwide and stands as one of the major global health challenges to be tackled. According to World Health Organization, about 400 million are having diabetes worldwide and it is the seventh leading cause of deaths in 2016. Plant-based natural products have been in use from ancient times as ethnomedicine for the treatment of several diseases, including diabetes. As a result of that, there are several reports on plant-based natural products displaying antidiabetic activity. In the current review, such antidiabetic potential compounds reported from all plant sources along with their chemical structures are collected, presented and discussed. These kinds of reports are essential to pool the available information to one source, followed by statistical analysis and screening to check the efficacy of all known compounds in a comparative sense. This kind of analysis can give rise to a few potential compounds from hundreds, which can further be screened through in vitro and in vivo studies, and human trails leading to the drug development.

METHODS

Phytochemicals, along with their potential antidiabetic property, were classified according to their basic chemical skeleton. The chemical structures of all the compounds with antidiabetic activities were elucidated in the present review. In addition to this, the distribution and their other remarkable pharmacological activities of each species are also included.

RESULTS

The scrutiny of literature led to the identification of 44 plants with antidiabetic compounds (70) and other pharmacological activities. For the sake of information, the distribution of each species in the world is given. Many plant derivatives may exert anti-diabetic properties by improving or mimicking insulin production or action. Different classes of compounds including sulfur compounds (1-4), alkaloids (5-11), phenolic compounds (12-17), tannins (18-23), phenylpropanoids (24-27), xanthanoids (28-31), amino acid (32), stilbenoid (33), benzofuran (34), coumarin (35), flavonoids (36-49) and terpenoids (50-70) were found to be potential active compounds for antidiabetic activity. Of the 70 listed compounds, majorly 17 compounds are obtained from triterpenoids, 13 from flavonoids and 7 from alkaloids. Among all the 44 plant species, the maximum number (7) of compounds were isolated from Lagerstroemia speciosa followed by Momordica charantia (6) and S. oblonga with 5 compounds.

CONCLUSION

This is the first paper to summarize the established chemical structures of phytochemicals that have been successfully screened for antidiabetic potential and their mechanisms of inhibition. The reported compounds could be considered as potential lead molecules for the treatment of type-2 diabetes. Further, molecular and clinical trials are required to select and establish therapeutic drug candidates.

Arecoline suppresses RANKL-induced osteoclast differentiation in vitro and attenuates LPS-induced bone loss in vivo

BACKGROUND

Areca nut has anti-inflammatory, antiparasitic, antihypertensive, and antidepressant properties. The pathological hallmarks of inflammatory joint diseases are an increased number of osteoclasts and impaired differentiation of osteoblasts, which may disrupt the bone remodeling balance and eventually lead to bone loss.

PURPOSE

The present study assessed the effects of arecoline, the main alkaloid found in areca nut, on osteoclast and osteoblast differentiation and function.

METHOD

M-CSF/RANKL-stimulated murine bone marrow-derived macrophages (BMMs) were incubated with several concentrations of arecoline, and TRAP staining and pit formation were assessed to monitor osteoclast formation. Quantitative real-time RT-PCR and western blot analyses were used to analyze the expression of osteoclast-associated genes and signaling pathways. The effects of arecoline on bone were investigated in an in vivo mouse model of lipopolysaccharide (LPS)-induced trabecular bone loss after oral administration of arecoline. Alizarin red S staining and assays to measure ALP activity and the transcription level of osteoblast-related genes were used to evaluate the effects of arecoline on osteoblast differentiation and bone mineralization.

RESULTS

In a dose-dependent manner, arecoline at concentrations of 50-100 μM reduced both the development of TRAP-positive multinucleated osteoclasts and the formation of resorption pits in M-CSF/RANKL-stimulated BMMs. In M-CSF/RANKL-stimulated BMMs, arecoline also suppressed the expression and translocation of c-Fos and NFATcl, and osteoclast differentiated-related genes via interference with the AKT, MAPK, and NF-kB activation pathways. Femur bone loss and microcomputed tomography parameters were recovered by oral administration of arecoline in the mouse LPS-induced bone loss model. Lastly, arecoline increased ALP activity, bone mineralization, and the expression of osteoblast differentiation-related genes, such as ALP and Runx2, in MC3T3-E1 cells.

CONCLUSION

Our data suggest that arecoline may attenuate or prevent bone loss by suppressing osteoclastogenesis and promoting osteoblastogenesis. These findings provide evidence supporting arecoline's use as a potential therapeutic agent in bone-loss disorders and diseases.

Arecoline inhibits pineal-testis function in experimentally induced hypothyroid rats

Arecoline is known to cause endocrine dysfunction. In the current article role of arecoline on pineal-testis activity was investigated in hypothyroid rats induced by propylthiouracil (PTU). PTU treatment caused thyroid dysfunction ultrastructurally with a fall in T₃ and T₄ levels followed by a rise of thyroid stimulating hormone (TSH) level. Pineal activity was impaired by PTU treatment, as evident from degenerated synaptic ribbons and mitochondria of the pinealocytes with depletion of pineal and serum N-acetyl serotonin and melatonin levels. Leydig cell function was suppressed, evident from reduced smooth endoplasmic reticulum and depletion of testosterone level. Sex accessories function was impaired by showing scanty rough endoplasmic reticulum with depletion of fructose and sialic acid levels. Arecoline treatment that caused pineal dysfunction and testicular stimulation in control rats, suppressed both pineal and testis functions after PTU treatment. The findings suggest that arecoline inhibits pineal-testis function in experimentally induced hypothyroid rats.

Melatonin as an inducer of arecoline and their coordinated roles in anti-oxidative activity and immune responses

Melatonin and it induced arecoline in arecoline play coordinated roles in immune responses.

ARECOLINE CANNOT ALTER PINEAL-TESTICULAR RESPONSES TO METABOLIC STRESS IN WISTAR RATS

Context

Betel nut is consumed by millions of people for stress reduction and increased capacity to work. One of its components is arecoline which is useful for Alzheimer and schizophrenia; it also influences endocrine and gonadal functions.

Objective

Objective is to examine whether arecoline can influence pineal-testicular function in metabolic stress.

Design

Rats were deprived of food or water or treated them with arecoline, each separately for 5 days.

Subjects

Pineal and testis with sex accessories were studied.

Methods

Ultrastructural (pineal, testis, Leydig cells and prostate), hormonal (melatonin and testosterone) and other parameters (fructose and sialic acid) were examined. Pineal indoleamines were quantitated by fluorometric method; testosterone by ELISA, and carbohydrate fractions by spectrophotometric methods.

Results

Inanition/ water deprivation caused pineal stimulation ultrastructurally (with enlarged synaptic ribbons) and elevation of melatonin level, but reproductive dysfunction by ultrastructural degeneration of Leydig cells and prostate with fall of testosterone, fructose and sialic acid concentrations. Arecoline treatment showed reversed changes to those of metabolic stress, but arecoline treatment in metabolic stress showed same results as in metabolic stress.

Conclusion

The findings suggest that arecoline cannot alter the action of metabolic stress on pineal-testicular activity in rats.

DUAL ACTION OF ARECOLINE ON ADRENAL FUNCTION AND GLUCOSE-GLYCOGEN HOMEOSTASIS IN METABOLIC STRESS IN MICE

Background

People chew betel nut (Areca catechu) for physical work and stress reduction, but it contains arecoline, which has both therapeutic value and untoward effects on endocrine and gonadal functions.

Objective

Aim of the present study is to investigate its role on adrenal with its target in metabolic stress in mice.

Materials and methods

Mice were deprived of water / food, each for 5 days / treated with arecoline (10 mg / kg body wt daily for 5 days) / arecoline after water or food deprivation, for 5 days each.

Results

Water or food-deprivation caused adrenocortical hyperactivity, evident from abundance of enlarged mitochondria and smooth endoplasmic reticulum (SER) with elevation of corticosterone level (C: 68.31 ± 2.30, WD: 159.31 ± 4.10 / FD: 194.12 ± 3.40 μg/ mL). Arecoline treatment alone or in water deprivation (C: 68.31 ± 2.30, AR: 144.50 ± 4.33, AR+WD: 194.42 ± 3.35 μg/ mL) / food deprivation (AR + FD: 180.89 ± 4.51 μg/ mL) stress also stimulated adrenocortical activity as recorded in metabolic stress. In contrast, adrenomedullary activity was not altered following water/ food deprivation. Arecoline treatment alone or in metabolic stress suppressed adrenomedullary activity by showing depletion of chromaffin granules (E/NE?), epinephrine (E) and norepinephrine (NE) concentrations. Both the stress decreased blood glucose and liver glycogen levels. Arecoline treatment decreased blood glucose level, with a rise in liver glycogen level, but elevated blood glucose level in water deprivation unlike in starvation.

Conclusion

Arecoline alone or in metabolic stress involves adrenal and probably other endocrine glands (pancreas, posterior pituitary and rennin-angiotensin system) to maintain homeostasis in metabolic stress in mice.

Arecoline aggravates hypothyroidism in metabolic stress in mice

Millions of people consume betel nut for increased capacity of work. It contains arecoline which is highly toxic and has several untoward side effects on endocrine functions. In this article, the role of arecoline on thyroid function under metabolic stress was investigated in mice. Water or food-deprivation, each for 5 days, caused ultrastructural degeneration of thyro-follicular cells, evident from pycnotic nuclei, scanty rough endoplasmic reticulum and mitochondria followed by depletion of blood serum T₃ and T₄ levels with alteration of TSH level as compared with control. Thyroid activity was also suppressed ultrastructurally as well as at hormonal level after arecoline administration. Further, arecoline treatment in water deprivation or food deprivation stress also caused thyroid dysfunction beyond that of metabolic stress, as evident from further ultrastructural degeneration of thyrocytes and depletion of thyroid hormones in mice. The findings suggest that arecoline aggravates hypothyroid condition in metabolic stress in mice.

RAS and sex differences in diabetic nephropathy

The incidence and progression of kidney diseases are influenced by sex. The renin-angiotensin system (RAS) is an important regulator of cardiovascular and renal function. Sex differences in the renal response to RAS blockade have been demonstrated. Circulating and renal RAS has been shown to be altered in type 1 and type 2 diabetes; this enzymatic cascade plays a critical role in the development of diabetic nephropathy (DN). Angiotensin converting enzyme (ACE) and ACE2 are differentially regulated depending on its localization within the diabetic kidney. Furthermore, clinical and experimental studies have shown that circulating levels of sex hormones are clearly modulated in the context of diabetes, suggesting that sex-dependent RAS regulation may be also be affected in these individuals. The effect of sex hormones on circulating and renal RAS may be involved in the sex differences observed in DN progression. In this paper we will review the influence of sex hormones on RAS expression and its relation to diabetic kidney disease. A better understanding of the sex dimorphism on RAS might provide a new approach for diabetic kidney disease treatment.