Cross Talk between Hydrogen Peroxide and Nitric Oxide in the Unicellular Green Algae Cell Cycle: How Does It Work?

The regulatory role of some reactive oxygen species (ROS) and reactive nitrogen species (RNS), such as hydrogen peroxide or nitric oxide, has been demonstrated in some higher plants and algae. Their involvement in regulation of the organism, tissue and single cell development can also be seen in many animals. In green cells, the redox potential is an important photosynthesis regulatory factor that may lead to an increase or decrease in growth rate.

Dysregulation of the Renin-Angiotensin-Aldosterone System (RAA) in Patients Infected with SARS-CoV-2-Possible Clinical Consequences.

SARS-CoV-2 impairs the renin-angiotensin-aledosterone system via binding ACE2 enzyme. ACE2 plays a key role in the biosynthesis of angiotensin (1-7), catalyzing the conversion of angiotensin 2 into angiotensin (1-7) and the reaction of angiotensin synthesis (1-9), from which angiotensin is (1-7) produced under the influence of ACE (Angiotensin-Converting Enzyme). Angiotensin 2 is a potent vasoconstrictor and atherogenic molecule converted by ACE2 to reducing inflammation and vasodilating in action angiotensin (1-7).

Up-regulation of PCSK9 gene expression and diminished level of LDL-receptor in rat liver as a potential cause of post-lipectomy hypercholesterolemia.

Studies designed to examine effects of fat mass reduction (including lipodystrophy and lipectomy) on human serum total and LDL-cholesterol concentrations are inconsistent. The purpose of this study was to examine effect of partial lipectomy in rats (as an experimental model of fat mass reduction in humans) on (1) circulating total cholesterol, LDL-cholesterol + VLDL-cholesterol and HDL-cholesterol concentrations, and (2) factors which may affect serum cholesterol concentrations such as: (a) liver LDL-receptor level, (b) expression of liver PCSK9 and (c) circulating PCSK9 concentration. Reduction of rat adipose tissue mass resulted in an increase in circulating total and LDL + VLDL-cholesterol concentrations, which was associated with (a) decrease in liver LDL-R level, (b) increase in liver PCSK9 expression, and (c) increase in circulating PCSK9 concentration as compared with sham controls.

Exogenously applied hydrogen peroxide modifies the course of the Chlamydomonas reinhardtii cell cycle.

The interaction of NO and HO in the regulation of plant development is well documented. We have recently shown that the content of NO and HO changes in a characteristic way during the cell cycle of Chlamydomonas reinhardtii (Pokora et al., 2017), which implies participation of these molecules in the regulation of Chlamydomonas development.

Changes in nitric oxide/hydrogen peroxide content and cell cycle progression: Study with synchronized cultures of green alga Chlamydomonas reinhardtii.

The present study aimed to evaluate the possible relationship between the changes in hydrogen peroxide (HO) and nitric oxide (NO) content and the course of growth and reproductive processes of the cell cycle of Chlamydomonas reinhardtii. The peak of HO observed at the beginning of the cell cycle was found to originate from Fe-SOD and Mn-SOD activity and result from the alternation in the photosynthetic processes caused by the dark-to-light transition of daughter cells. A rapid increase in NO concentration, observed before the light-to-dark cell transition, originated from NR and NIR activity and was followed by a photosynthesis-independent, Mn-SOD-mediated increases in HO production.

Improved glucose metabolism following bariatric surgery is associated with increased circulating bile acid concentrations and remodeling of the gut microbiome.

Clinical studies have indicated that circulating bile acid (BA) concentrations increase following bariatric surgery, especially following malabsorptive procedures such as Roux-en-Y gastric bypasses (RYGB). Moreover, total circulating BA concentrations in patients following RYGB are positively correlated with serum glucagon-like peptide-1 concentrations and inversely correlated with postprandial glucose concentrations. Overall, these data suggest that the increased circulating BA concentrations following bariatric surgery - independently of calorie restriction and body-weight loss - could contribute, at least in part, to improvements in insulin sensitivity, incretin hormone secretion, and postprandial glycemia, leading to the remission of type-2 diabetes (T2DM).

Upregulation of Pnpla2 and Abhd5 and downregulation of G0s2 gene expression in mesenteric white adipose tissue as a potential reason for elevated concentration of circulating NEFA after removal of retroperitoneal, epididymal, and inguinal adipose tissue.

Elevated concentrations of circulating non-esterified fatty acids (NEFA) were reported in (a) humans with lipodystrophy, (b) humans following bariatric surgery, and (c) transgenic mice with reduced amounts of adipose tissue. Paradoxically, these findings suggest that the reduction of adipose tissue mass is associated with elevated circulating NEFA concentrations. To explain a molecular background of this phenomenon, we analyzed the effects of surgical removal of inguinal, epididymal, and retroperitoneal white adipose tissue (WAT) on (a) circulating NEFA concentrations, (b) expression of Pnpla2, a gene that encodes adipose triglyceride lipase (ATGL), genes encoding abhydrolase domain containing 5 (ABHD5) and G0/G1 switch 2 (G0S2), i.

Up-Regulation Mttp and Apob Gene Expression in Rat Liver is Related to Post-Lipectomy Hypertriglyceridemia.

Background/aims: The aim of this study was to explain the molecular basis for elevated concentrations of circulating triglycerides (TAGs) after partial surgical removal of adipose tissue (lipectomy) in rats.

Methods: The levels of mRNA and protein: a) involved in synthesis of fatty acids and TAGs; b) participating in TAG-rich lipoproteins assembly and secretion; and c) transcription factors essential for maintaining TAG homeostasis were determined by RT-PCR and Western Blot in the livers of control and lipectomized rats.

Results: Partial lipectomy was associated with increase: a) in serum and liver concentration of TAGs, and b) in the liver levels of mRNA of microsomal TAG transfer protein (MTP) and apolipoprotein B-100 (ApoB- 100).

Time-dependent changes in antioxidative enzyme expression and photosynthetic activity of Chlamydomonas reinhardtii cells under acute exposure to cadmium and anthracene.

Heavy metals (HM) and polycyclic aromatic hydrocarbons (PAHs) are present in the freshwater environment at concentrations that can be hazardous to the biota. Among HMs and PAHs, cadmium (Cd) and anthracene (ANT) are the most prevalent and toxic ones. The response of Chlamydomonas cells to Cd and ANT at concentrations that markedly reduced the growth of algal population was investigated in this study.

Sensitivity of natural killer cells to activation in the process of ageing is related to the oxidative and inflammatory status of the elderly.

The role of the innate immunity during human ageing is not well understood. The aim of the study was to estimate reactivity of NK (natural killer) cells in the very old (mean age 91 years) and old subjects (mean age 78 years) compared to young individuals (mean age 26 years) in respect to the indices of the oxidative stress (telomere length of NK cells, serum content of -H groups), serum total antioxidant status and serum concentrations of interleukin 6 and tumor necrosis factor-α (TNF-α). The activation state of NK cells, reflected by telomerase activity and intracellular interferon γ (IFNγ) content, was also measured.

[Genetic basis of dyslipidemia].

Genetic disorders play an important role in the ethiopathogenesis of disease processes in humans. In the present paper we have described documented genes polymorphisms associated with dyslipidemia. Some of them have been known for years, but some have been discovered quite recently.

Successful ageing of nonagenarians is related to the sensitivity of NK cells to activation.

NK cells are a component of innate immunity which activity significantly correlates with health status. The aim of our study was to estimate a status of NK (natural killer) cells in the very old (mean age 92+/-2 ys) and old subjects (mean age 78+/-5 ys) as compared to a control group of young individuals (mean age 25+/-4 ys). NK cells were characterized by measurement of their cytotoxic activity, expression of intracellular interferon gamma, telomere length and telomerase activity in resting and activated cells.

Increased serum resistin concentration in patients with chronic pancreatitis: possible cause of pancreatic fibrosis.

Background: Resistin is an adipokine, which displays proinflammatory properties. Thus, it is likely that resistin can influence the course of chronic pancreatitis, and/or that chronic pancreatitis may affect the serum resistin concentration.

Goals: The aim of the present study was to determine the serum resistin concentration in patients with chronic pancreatitis and to analyze the relationship between serum resistin concentration and serum concentrations of leptin (proinflammatory adipokine) and adiponectin (anti-inflammatory adipokine).

Telomerase activity in urine sediments as a tool for noninvasive detection of bladder cancer.

Telomerase is extensively investigated as potential diagnostic and prognostic marker in human tumors. In this study, we determined telomerase activity in histological specimens and voided urine of 52 human bladder cancers. Using the PCR-ELISA method telomerase activity was found in 21 (88%) of the 24 tumor tissues and in the corresponding sediments from voided urine of patients with superficial bladder carcinoma (Ta/T1).

[Photodynamic diagnosis and therapy of bladder cancer].

High frequency of bladder cancer in polish population and relatively low sensitivity of cancer detection in early stages is a main reason for search for other, more sensitive diagnostic tests. Photodynamic diagnosis based on accumulation of photosensitizers, porphirin derived compounds emitting fluorescence in laser light is a promising tool for detecting of small or poorly differentiated neoplastic changes. On the other hand we can use photodynamic therapy when in laser light photosensitizers generate free oxygen radicals and destroy neoplastic tissue.

Increased activity of glycerol 3-phosphate dehydrogenase and other lipogenic enzymes in human bladder cancer.

Common molecular changes in cancer cells are high carbon flux through the glycolytic pathway and overexpression of fatty acid synthase, a key lipogenic enzyme. Since glycerol 3-phosphate dehydrogenase creates a link between carbohydrates and the lipid metabolism, we have investigated the activity of glycerol 3-phosphate dehydrogenase and various lipogenic enzymes in human bladder cancer. The data presented in this paper indicate that glycerol 3-phosphate dehydrogenase activity in human bladder cancer is significantly higher compared to adjacent non-neoplastic tissue, serving as normal control bladder tissue.