Rafat Siddiqui | Virginia State University (original) (raw)

Papers by Rafat Siddiqui

Journal of Inflammation Research, 2012

Niacin, also known as nicotinic acid, is an organic compound that has several cardiobeneficial ef... more Niacin, also known as nicotinic acid, is an organic compound that has several cardiobeneficial effects. However, its use is limited due to the induction of a variable flushing response in most individuals. Flushing occurs from a niacin receptor mediated generation of prostaglandins from arachidonic acid metabolism. This study examined the ability of docosahexaenoic acid, eicosapentaenoic acid, and omega-3 polyunsaturated fatty acids (PUFAs), to attenuate niacin-induced prostaglandins in THP-1 macrophages. Niacin induced both PGD 2 and PGE 2 generation in a dose-dependent manner. Niacin also caused an increase in cytosolic calcium and activation of cytosolic phospholipase A 2. The increase in PGD 2 and PGE 2 was reduced by both docosahexaenoic acid and eicosapentaenoic acid, but not by oleic acid. Omega-3 PUFAs efficiently incorporated into cellular phospholipids at the expense of arachidonic acid, whereas oleic acid incorporated to a higher extent but had no effect on arachidonic acid levels. Omega-3 PUFAs also reduced surface expression of GPR109A, a human niacin receptor. Furthermore, omega-3 PUFAs also inhibited the niacin-induced increase in cytosolic calcium. Niacin and/or omega-3 PUFAs minimally affected cyclooxygenase-1 activity and had no effect on cyclooxygenase-2 activity. The effects of niacin on PGD 2 generation were further confirmed using Langerhans dendritic cells. Results of the present study indicate that omega-3 PUFAs reduced niacin-induced prostaglandins formation by diminishing the availability of their substrate, as well as reducing the surface expression of niacin receptors. In conclusion, this study suggests that the regular use of omega-3 PUFAs along with niacin can potentially reduce the niacin-induced flushing response in sensitive patients.

Food & Nutrition Research

Background: Obesity is the underlying risk factor for major metabolism complications, including n... more Background: Obesity is the underlying risk factor for major metabolism complications, including non-alcoholic-fatty liver disease, atherosclerosis, and cardiovascular disease. The adipose tissue is a vital endocrine organ that plays a role in the synthesis and storage of lipid and, therefore, is a contributory factor to the development and progression of obesity. A growing interest in nutraceuticals suggests that natural products can alleviate the risk factors and may be effective in mitigating obesity. Aim: The objective of this study was to examine the underlying mechanisms of immature ginger on adipocyte differentiation and lipogenesis in a 3T3-L1 cellular model. Methods: Ginger samples, extracted in 80% methanol, were dried and resuspended in DMSO at 50 μg/mL as stock solution. For analysis, the extracted samples were further diluted in media. Effects on adipogenesis were evaluated by determining lipid droplet and triglyceride accumulation, whereas effects on lipogenesis were de...

Food Science and Nutrition, 2018

The digestive tract is made up of the esophagus, stomach, and the small and large intestines.The ... more The digestive tract is made up of the esophagus, stomach, and the small and large intestines.The colon is part of the body’s digestive tract which processes nutrients from foods and helps pass waste material out of the body. The colon is the first part of the large intestine and is about 5 feet long. Colorectal cancer (CRC) begins when the process of normal replacement of the lining cells of the colon is deregulated. Errors in normal checks and balances that control growth during cell division transform a normal cell causing it to divide and grow uncontrollably and contribute to growth within the colon known as polyps. Polyps are precancerous lumps that grow slowly over a long period; however, the subsequent genetic mutations in these cells make then invasive and malignant [1]. Colorectal cancers are the third most common causes of cancers in the United States in both women and men. For 2018, the American Cancer Society’s estimates 97,220 new cases of colon cancer and 43,030 new cas...

Current Developments in Nutrition, 2020

Objectives The long-term objective of present research is to evaluate papaya for anti-diabetic pr... more Objectives The long-term objective of present research is to evaluate papaya for anti-diabetic properties. The current objectives were (1) To determine polyphenolic contents and antioxidation activity of leaves, skin, pulp, and seeds of green and yellow papaya and (2) to evaluate their effects on glucose uptake in HepG2 liver cells. Methods The leaves, skin, pulp, and seeds samples were freeze dried and then extracted in water or 80% Methanol. The total phenolic contents of each extracted sample was determined using the Folin- Ciocalteu method. The antioxidation activity in each sample was determined using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and Ferric ion reducing antioxidation power (FRAP) assays. Effect of each fraction on glucose uptake was determined using a fluorescent-tagged NBD-Glucose derivative. Results The concertation of polyphenols was highest in both water and methanol extracts of seeds from yellow papaya compared to that in seeds from green papaya. Leaves and skin fr...

Growth, development, and aging : GDA, 1992

Growth allometry was examined over the range 6 to 112 days of age in male and female mice from li... more Growth allometry was examined over the range 6 to 112 days of age in male and female mice from lines selected for low (L) or high (H) plasma concentrations of insulin-like growth factor-I (IGF-I). Plasma IGF-I concentrations were greater in the H line than in L line mice from 28 days of age. H line mice also had greater liveweights and weights of the heart, kidneys, pancreas, lungs, liver, brain and testes from 21-28 days of age. Changes in weights of these organs reflected the general pattern of body growth, there being no consistent effects of selection line on allometric growth coefficients. Ovarian weights were not different between the lines. For muscle weights, (gastrocnemius, quadriceps femoris), the weights or lengths of bones (tibia, femur) and the nose-anus and anus-tail lengths, allometric growth coefficients were generally higher (P less than .05) in L line females than in L line males or H line mice of either sex. The allometric growth coefficient for spleen was signifi...

東京工業高等専門学校研究報告書, Jan 10, 2006

SARS-CoV-2 has caused a global pandemic with limited treatment options available. Some studies ha... more SARS-CoV-2 has caused a global pandemic with limited treatment options available. Some studies have proposed that vitamin D may be associated with Covid-19 infection outcomes. The aim of this literature review is to analyze the evidence currently available from Randomized Controlled Trials (RCTs) and quasi-experimental studies regarding the impact of vitamin D used as a preventative or adjunctive therapeutic agent on the disease severity and mortality rate of Covid-19 patients. A literature search was performed using PubMed, Science Direct, and ProQuest. Sources listed in the citations of systematic reviews and meta-analyses were also evaluated. Articles meeting the inclusion criteria were selected after title, abstract, and article content were reviewed. Five studies, including two RCTs, met inclusion criteria. One RCT did not find significant benefit with vitamin D3 supplementation. The remaining studies, including mostly elderly participants using various vitamin D supplementatio...

Nutrients

Quinoa (Chenopodium quinoa Willd.) is a nutrient-rich grain native to South America and eaten wor... more Quinoa (Chenopodium quinoa Willd.) is a nutrient-rich grain native to South America and eaten worldwide as a healthy food, sometimes even referred to as a ”superfood”. Like quinoa grains, quinoa greens (green leaves, sprouts, and microgreens) are also rich in nutrients and have health promoting properties such as being antimicrobial, anticancer, antidiabetic, antioxidant, antiobesity, and cardio-beneficial. Quinoa greens are gluten-free and provide an excellent source of protein, amino acids, essential minerals, and omega-3 fatty acids. Quinoa greens represent a promising value-added vegetable that could resolve malnutrition problems and contribute to food and nutritional security. The greens can be grown year-round (in the field, high tunnel, and greenhouse) and have short growth durations. In addition, quinoa is salt-, drought-, and cold-tolerant and requires little fertilizer and water to grow. Nevertheless, consumption of quinoa greens as leafy vegetables is uncommon. To date, o...

Cachexia is defined as progressive wasting of body tissues, primarily muscle and adipose tissue. ... more Cachexia is defined as progressive wasting of body tissues, primarily muscle and adipose tissue. Cachexia is a major cause of morbidity and mortal-ity in patients with a large variety of diseases that include cancer, infection, heart failure, chronic obstructive pulmonary disease, acquired immune deficiency syndrome (AIDS), arthritis, and surgery. In many forms of chronic illness, cachexia accounts for much of the increased morbidity and mortality. In addition to effects upon mortality and disease complications, cachexia is commonly associated with decreased quality of life that includes weakness, fatigue, and lack of interest in life-associated activ-ities. Anorexia frequently accompanies cachexia and can contribute significantly to tissue loss (ie, anorex-

Nutrients

The term “nutraceuticals” is derived from “nutrition” and “pharmaceuticals” and is used fornutrit... more The term “nutraceuticals” is derived from “nutrition” and “pharmaceuticals” and is used fornutrition products that are also used as medicine [1] [...]