Type-1 diabetes: Lessons from a decade of preclinical studies on phytotherapy

BACKGROUND

In recent decades, numerous herbal products have been shown to have antihyperglycemic and beta cell-regenerative effects in animal studies. However, there is no clinical evidence that those products completely cure patients with type-1 diabetes (T1D). Therefore, it seems that most of the phytochemicals do not have a significant impact on human beta cells, and the results of experimental studies conducted on them may not be generalizable to the clinic.

PURPOSE

The present work aims to review extensively the methods and results of preclinical studies on phytotherapy of T1D published in the last 10 years.

METHODS

This paper critically analyzes the designs of studies, treatment protocols, methods of diabetes induction, characteristics of the studied animals, clinical relevance, reproducibility of research, and other aspects related to conducting preclinical studies on T1D. We discussed limitations that make many of the results of these studies not generalizable to the clinic. Finally, some recommendations were given to improve studies on the phytotherapy of T1D to avoid misleading interpretations about the antidiabetic effect of herbal compounds.

CONCLUSION

This paper can be considered a practical guide for researchers interested in the field of phytotherapy of T1D to increase the reliability, reproducibility, and validity of their preclinical studies.

Cytotoxic and apoptotic effects of Ferula gummosa Boiss: extract on human breast adenocarcinoma cell line

PURPOSE

Ferula gummosa Boiss. is a well-known and valuable medicinal plant in Iran. Research has shown that this plant has several pharmacological properties, including anti-bacterial, anti-cancer and etc. In the present study, we investigated the cytotoxic properties of F. gummosa Boiss. extract in MCF-7 breast adenocarcinoma cells.

METHODS

The cytotoxicity and pro-apoptotic properties of the extract were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test and propidium iodide (PI) stained cells, respectively. Apoptosis and necrosis were evaluated by annexin V-PI staining. The levels of reactive oxygen species (ROS),malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) was determined to evaluate oxidative stress. The cell migration and the gene expression were assessed by scratch assay and quantitative real-time polymerase chain reaction (q-RT-PCR), respectively.

RESULTS

The extract of F. gummosa decreased the viability and cell cycle progression of MCF-7 cells by inducing apoptosis and necrosis, increasing ROS and MDA levels, and decreasing GSH levels and SOD activity. It also lowered the cells' migration capability by enhancing p53 mRNA levels and reducing MMP-9 mRNA expression.

CONCLUSION

F. gummosa exhibited pro-apoptotic, anti-proliferative, and anti-metastatic effects on MCF-7 cells. It is therefore recommended that detailed future research be done on different parts of the plant or its secondary metabolites to find anti-cancer lead compounds.

Pro-apoptotic effect of chloroform fraction of Moraea sisyrinchium bulb against glioblastoma cells

INTRODUCTION

Glioblastoma is a common malignant brain tumor, with limited therapeutic options. In our previous study, the Moraea sisyrinchium plant showed cytotoxicity against glioblastoma and hepatocellular carcinoma cells. Among different parts of this plant (flower, stem, and bulb), the bulb showed better anticancer potential. The present work aimed to test the anticancer activity of different fractions of the bulb extract, to determine its phytochemicals, and to study its mechanism action on glioblastoma.

METHODS

The bulb extract was partitioned into different fractions using immiscible solvents. The U87 glioblastoma cells were incubated with the obtained fractions. Then, the cell proliferation assay (MTT), cell migration test (scratch), cell cycle analysis (propidium iodide staining), apoptosis/necrosis assay (annexin V/propidium iodide staining), and real-time PCR (PTEN, Akt, mTOR, BAX and BCL-2 genes) were performed. Phytochemicals were determined using liquid chromatography-mass spectroscopy.

RESULTS

The chloroform fraction showed more antiproliferative effect than n-hexane, ethyl acetate, and n-butanol fractions. Also, chloroform fraction induced cell cycle arrest, increased apoptosis, and inhibited cell migration ability (P < 0.05). The expression of PTEN, mTOR, and BAX genes was significantly up-regulated, while the expression of Akt and Bcl-2 showed down-regulation. The phytochemicals identified in the chloroform fraction were mainly xanthones, phytosterols, and isoflavones.

CONCLUSION

The chloroform fraction of Moraea sisyrinchium bulb inhibits the proliferation and migration of glioblastoma cells by inducing cell cycle arrest and apoptosis by upregulation of the PTEN gene and Bax/Bcl-2 ratio. The identified compounds in the chloroform fraction are potential candidates for further investigation as anticancer agents against glioblastoma.

The Effect of Statins on the Differentiation and Function of Central Nervous System Cells

Statins (3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) reduce plasma cholesterol and improve endothelium-dependent vasodilation, inflammation, and oxidative stress. The effect of statins on the central nervous system (CNS), particularly on cognition and neurological disorders such as cerebral ischemic stroke, multiple sclerosis (MS), and Alzheimer's disease (AD), has received increasing attention in recent years, both within the scientific community and in the media. This review aims to provide an updated discussion on the effects of statins on the differentiation and function of various nervous system cells, including neurons and glial cells. Additionally, the mechanisms of action and how different types of statins enter the CNS will be discussed.

Neuro-protective Effect of Acetyl-11-keto-β-boswellic Acid in a Rat Model of Scopolamine-induced Cholinergic Dysfunction

BACKGROUND

Acetyl-11-keto-β-boswellic acid (AKBA) is a major component of the oleo-gum resin of B. serrata with multiple pharmacological activities. The objective of this study was to explore the underlying mechanisms of neuroprotective potential of AKBA against scopolamine-mediated cholinergic dysfunction and memory deficits in rats.

METHODS

The rats received AKBA (2.5, 5, and 10 mg/kg, oral) for 21 days. In the third week, scopolamine was administered 30 min before the Morris water maze and passive avoidance tests. In order to perform biochemical assessments, the hippocampus and prefrontal cortex were extracted from the rats euthanized under deep anesthesia.

RESULTS

In the MWM test, treatment with AKBA (5 and 10 mg/kg) decreased the latency and distance to find the platform. Moreover, in the PA test, AKBA remarkably increased latency to darkness and stayed time in lightness while decreasing the frequency of entry and time in the darkness. According to the biochemical assessments, AKBA decreased acetylcholinesterase activity and malondialdehyde levels while increasing antioxidant enzymes and total thiol content. Furthermore, AKBA administration restored the hippocampal mRNA and protein levels of brain-derived neurotrophic factor (BDNF) and mRNA expression of B-cell lymphoma (Bcl)- 2 and Bcl-2- associated X genes in brain tissue of scopolamine-injured rats.

CONCLUSION

The results suggested the effectiveness of AKBA in preventing learning and memory dysfunction induced by scopolamine. Accordingly, these protective effects might be produced by modulating BDNF, cholinergic system function, oxidative stress, and apoptotic markers.

Edible Herbal Medicines as an Alternative to Common Medication for Sleep Disorders: A Review Article

Insomnia is repeated difficulty in falling asleep, maintaining sleep, or experiencing lowquality sleep, resulting in some form of daytime disturbance. Sleeping disorders cause daytime fatigue, mental confusion, and over-sensitivity due to insufficient recovery from a sound sleep. There are some drugs, such as benzodiazepines and anti-histaminic agents, which help to sleep induction and insomnia cure. However, the prolonged administration is unsuitable because of tolerance and dependence. Therefore, the researchers attempt to find new medicines with lesser adverse effects. Natural products have always been good sources for developing new therapeutics for managing diseases such as cancer, cardiovascular disease, diabetes, insomnia, and liver and renal problems. Ample research has justified the acceptable reason and relevance of the use of these herbs in the treatment of insomnia. It is worth noting that in this study, we looked into various Persian herbs in a clinical trial and in vivo to treat insomnia, such as Artemisia annua, Salvia reuterana, Viola tricolor, Passiflora incarnata, lettuce, and Capparis spinose. According to research, herb extracts and fractions, particularly n-butanol fractions with non-polar agents, impact the benzodiazepine receptors and have hypnotic properties. Also, alkaloids, glycosides, flavonoids, saponins, and tannins in practically every plant are mentioned making them the popular natural compounds to help with sleep disorders and promote calmness.

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

Heavy metals in contact dermatitis: A review

Contact dermatitis is an inflammatory skin reaction caused by direct contact with chemical substances in the environment and can either be irritant or allergic in nature. The clinical symptoms of contact dermatitis, include local skin rash, itching, redness, swelling, and lesions. Nowadays, 15-20% of people have some degree of contact dermatitis, which can be more or less severe. Immune responses in allergic contact dermatitis (ACD) are due to the effects of cytokines and allergen-specific CD4⁺ and CD8⁺ T cells on the skin. Acids and alkalis such as drain cleaners, plants such as poinsettias, hair colors, and nail polish remover, are all prominent causes of irritant contact dermatitis (ICDs). Heavy metals are metallic elements with a high atomic weight that are hazardous in low quantities and are known to cause dermatitis after systemic or local exposure. Nickel (Ni), chromium (Cr), lead (Pb), and copper (Cu) are among the most common heavy metals used in various industries. Metal allergies may cause ACD and also systemic contact dermatitis (SCD). Contact dermatitis is detected by laboratory tests such as patch testing, lymphocyte stimulation test (LST), and evaluation of cytokine production by primary cultures of peripheral blood mononuclear cells. This article presents an update on the epidemiological and clinical characteristics of ACD and SCD caused by three heavy metals (Cr, Cu, and Pb). Ni is not discussed due to recent coverage. Furthermore, the effects of contact sensitivity to some other heavy metals, such as gold (Au), cobalt (Co), palladium (Pd), and mercury (Hg) are discussed.

The therapeutic potential of Panax ginseng and Ginger on postsurgical adhesion band formation

Background:

Peritoneal adhesions (PA) are a common complication of abdominal operations. Previous studies indicate that inhibition of inflammation and fibrosis at sites of peritoneal damage may prevent the development of intra-abdominal adhesions. Zingiber officinalis Roscoe (ginger) and Panax ginseng (p. ginseng) are herbal products with antioxidant and anti-inflammatory effects which can have restorative properties.

Objective:

This research aimed to examine the impact of ginger and p. ginseng on prevention of PA in a rat model after surgery.

Methods:

Following a laparotomy, the wall of the cecum was rubbed to induce intra-abdominal adherence in Wistar rats. Ginger (400mg/kg) and p. ginseng (500mg/kg) were administered to the animals. The animals were sacrificed on 10 days after surgery, and the Nair and Leach scoring system was used to assess adhesion. The microscopic histology of the induced cecal adhesions was evaluated. An enzyme-linked immunosorbent assay (ELISA) was used to determined tissue levels of transforming growth factor-beta (TGF-β) on homogenized PA tissue. Real-time PCR was performed to quantify the mRNA expression of IL-1β, TNF-α, Col 1a1, and Col 3a1 in rat tissue.

Result:

The adhesion score and histopathological rating based on the Nair and Leach scoring criteria showed lower adhesion scores in the group of rats treated with p. ginseng compared to the control group (P<0.05). Treatment with ginger and p. ginseng was associated with reduced tissue level of TGF-β and mRNA expression of TNF-α and IL-1β. The gene expression level of Col 1a1 and Col 3a1 were markedly decreased in the p. ginseng group.

Conclusion:

The study's outcome recommends that p. ginseng could be an effective agent for preventing the PA and inflammation during the post-operative stage.

Protective effect of Artemisia absinthium extract against glutamate-induced toxicity in PC12 cells

Objective[s]:

Glutamatergic dysfunction, has been implicated in the pathogenesis of numerous central nervous system disorders. Artemisia absinthium [A. absinthium], has been reported to have neuroprotective and antioxidant activities. In the current study, the effect of A. absinthium extract on glutamate-induced cytotoxicity was examined using PC12 cells.

Methods:

PC12 cells were pretreated with A. absinthium extract [70% ethanol] at concentration ranges of 6.25-25 µg/ml for 2 h, followed by exposure to glutamate [8 mM] for 24 hr. The cells viability, reactive oxygen species [ROS] accumulation, and lipid peroxidation were measured. Moreover, propidium iodide flow cytometry assay was performed for assessment of apoptosis.

Results:

Pretreatment with A. absinthium extract markedly attenuated the loss of cell viability, ROS generation, lipid peroxidation, and cell apoptosis in glutamate-injured PC-12 cells.

Conclusion:

Our results indicate that A. absinthium extract protects PC12 cells against glutamate-induced injury possibly through reducing oxidative stress and apoptosis.

SARS-CoV-2 triggering autoimmune diseases

Autoimmunity, hyperstimulation of the immune system, can be caused by a variety of reasons. Viruses are thought to be important environmental elements that contribute to the development of autoimmune antibodies. It seems that viruses cause autoimmunity with mechanisms such as molecular mimicry, bystander activation of T cells, transient immunosuppression, and inflammation, which has also been seen in post-Covid-19 autoimmunity. Infection of respiratory epithelium by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dysregulates the immune response, triggers both innate and acquired immunity that led to the immune system's hyperactivation, excessive cytokine secretion known as “cytokine storm,” and finally acute respiratory distress syndrome (ARDS) associated with high mortality. Any factor in the body that triggers chronic inflammation can contribute to autoimmune disease, which has been documented during the Covid-19 pandemic. It has been observed that some patients produce autoantibody and autoreactive CD4⁺ and CD8⁺ T cells, leading to the loss of self-tolerance. However, there is a scarcity of evidence defining the precise molecular interaction between the virus and the immune system to elicit autoreactivity. Here, we present a review of the relevant immunological findings in Covid-19 and the current reports of autoimmune disease associated with the disease.

The impact of lymphoid memory cells in different ages of COVID-19 patients

Coronaviruses are highly pathogenic and transmissible viruses. The SARS-CoV-2 virus that emerged in December 2019 is increasingly recognized as a serious, worldwide public health concern. Respiratory infections and the hyper-inflammatory response induced by SARS-CoV-2 play a key role in disease severity and death in infected COVID-19 patients. However, much uncertainty still exists about the pathogenesis and various effects of COVID-19 on immune system. It seems that memory T cells can reduce the severity of COVID-19 infection by inducing a protective immune response. Memory T cells along with protective antibodies are the main defenses and also protective barrier against recurrent COVID-19 infection. The role of Memory T cells varies in different ages and the severity of COVID-19 infection varies between children, adults and the elderly. Furthermore, the aim of this review is to evaluate the role of memory cells in mild, moderate and severe infected COVID-19 patients with different ages.

The role of statins in the differentiation and function of bone cells

BACKGROUND

Statins are 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors blocking cholesterol biosynthesis in hepatic cells, thereby causing an increase in low-density lipoprotein (LDL) receptors resulting in enhanced uptake and clearance of atherogenic LDL-cholesterol (LDL-C) from the blood. Accordingly, statins decrease the risk of developing atherosclerosis and its acute complications, such as acute myocardial infarction and ischaemic stroke. Besides the LDL-C-lowering impact, statins also have other so-called pleiotropic effects. Among them, the ability to modulate differentiation and function of bone cells and exert direct effects on osteosynthesis factors. Specifically, earlier studies have shown that statins cause in vitro and in vivo osteogenic differentiation.

DESIGN

The most relevant papers on the bone-related 'pleiotropic' effects of statins were selected following literature search in databases and were reveiwed.

RESULTS

Statins increase the expression of many mediators involved in bone metabolism including bone morphogenetic protein-2 (BMP-2), glucocorticoids, transforming growth factor-beta (TGF-β), alkaline phosphatase (ALP), type I collagen and collagenase-1. As a result, they enhance bone formation and improve bone mineral density by modulating osteoblast and osteoclast differentiation.

CONCLUSION

This review summarizes the literature exploring bone-related 'pleiotropic' effects of statins and suggests an anabolic role in the bone tissue for this drug class. Accordingly, current knowledge encourages further clinical trials to assess the therapeutic potential of statins in the treatment of bone disorders, such as arthritis and osteoporosis.

Molecular Insights into COVID-19 Pathophysiology, Immune Pathogenesis, Detection, and Treatment

In late December 2019, a new kind of Coronavirus called severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) was officially identified in Wuhan, China. In March 2020, SARS-CoV-2 was declared a pandemic by the World Health Organization (WHO), and it has infected millions of people worldwide. SARS-CoV-2 is a highly contagious Coronavirus, which has led to an outbreak of acute respiratory tract infection called "Coronavirus disease 2019" (COVID-19), resulting in mild to severe respiratory infections in humans. The design of appropriate therapeutic approaches is dependent on the understanding of molecular and cellular pathways of Coronavirus infections. In this study, we summarized the characteristic features of SARS-CoV-2. In addition, we considered the recent information regarding COVID-19 molecular immune pathogenesis, diagnosis, and potential treatment, which may provide novel perspectives and therapeutic goals in combating SARS-CoV-2.

Association between vitamin D receptor gene FokI and TaqI variants with autism spectrum disorder predisposition in Iranian population

BACKGROUND AND AIM

Autism spectrum disorder (ASD) is one of the neurodevelopmental and cognitive conditions that involves 1 in 160 children around the world. Several studies showed that there is a relationship between vitamin D receptor (VDR) gene polymorphisms with the neurodevelopmental behavioral disorders. In the current study, we aimed to highlight the association of VDR gene polymorphisms (FokI and TaqI) with the risk of autism in Birjand population.

MATERIAL AND METHODS

In this case-control study eighty-one patients recognized with ASD and one hundred-eight healthy controls were recruited to the study from 2017 to 2018. Genotyping was carried out by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) technique for all subjects.

RESULTS

Calculated odds ratio and P-value for the alleles of VDR gene FokI and TaqI variants between autistic patients and controls did not show a significant difference (P > 0.05). However, calculated homozygous recessive (tt) for TaqI polymorphism was statistically significant (P = 0.015) in control group and there was also statistically meaningful difference in both case and control groups in ft haplotype (P = 0.04).

CONCLUSION

These results provide preliminary evidence that genetic variants of the VDR gene (FokI and TaqI) might have a possible reduced risk of ASD occurrence in children. The additional examination is needed to acquire more decisive and precise results in this area.