Fluro-Protein C-Phycocyanin Docked Silver Nanocomposite Accelerates Cell Migration through NFĸB Signaling Pathway.

Currently, there is a great demand for the development of nanomedicine aided wound tissue regeneration via silver doped nanoceuticals. Unfortunately, very little research is being carried out on antioxidants-doped silver nanometals and their interaction on the signaling axis during the bio-interface mechanism. In this study, c-phycocyanin primed silver nano hybrids (AgcPCNP) were prepared and analyzed for properties such as cytotoxicity, metal decay, nanoconjugate stability, size expansion, and antioxidant features. Fluctuations in the expression of marker genes during cell migration phenomena in in vitro wound healing scenarios were also validated. Studies revealed that physiologically relevant ionic solutions did not exhibit any adverse effects on the nanoconjugate stability. However, acidic, alkali, and ethanol solutions completely denatured the AgcPCNP conjugates. Signal transduction RT2PCR array demonstrated that genes associated with NFĸB- and PI3K-pathways were significantly (p < 0.5%) altered between AgcPCNP and AgNP groups. Specific inhibitors of NFĸB (Nfi) and PI3K (LY294002) pathways confirmed the involvement of NFĸB signaling axes. In vitro wound healing assay demonstrated that NFĸB pathway plays a prime role in the fibroblast cell migration. In conclusion, the present investigation revealed that surface functionalized AgcPCNP accelerated the fibroblast cell migration and can be further explored for wound healing biomedical applications.

Retinoic acid abrogates LPS-induced inflammatory response via negative regulation of NF-kappa B/miR-21 signaling.

CONTEXT: Macrophages are essential components of the immune system, with significant roles in inflammation modulation. They can be activated into pro-inflammatory M1 or anti-inflammatory M2 phenotypes, depending on their micro-environment. Molecular factors that modulate macrophage polarization are hot targets for therapeutic strategies to counter chronic inflammatory pathological conditions. OBJECTIVE: The current study aimed to elucidate the molecular mechanisms by which Retinoic acid (RA), a potent immunomodulator, suppresses LPS-induced inflammatory response in macrophages. MATERIALS AND METHODS: RAW 264.7 macrophages were treated with RA and/or LPS, and analyzed for inflammatory genes and miR-21 by PCR. The roles of miR-21 and NF-ĸB signaling pathway were also assessed by knock-down experiments, immunofluorescence, and ChIP assays. RESULTS: Pretreatment with RA quenched the LPS-induced inflammatory responses, including phagocytosis, ROS generation, and NO production. RA shifted the polarization away from the M1 state by negative regulation of IKKα/ß, p65, and miR-21. RA hindered the phosphorylation of IKKα/ß, translocation of p65 into the nucleus, and the subsequent upregulation of miR-21. Knock-in and knock-down experiments showed that miR-21 is central for the polarization shift toward the pro-inflammatory M1 state. CONCLUSION: miR-21 is involved in the LPS-induced pro-inflammatory profile of macrophages and that RA negatively regulates the inflammatory response by targeting NF-ĸB/miR-21 signaling. Our data exposes RA's potential as a pharmacological agent to manipulate miR-21 and counteract hyper-inflammatory response.

Nanoceutical Adjuvants as Wound Healing Material: Precepts and Prospects.

Dermal wound healing describes the progressive repair and recalcitrant mechanism of 12 damaged skin, and eventually, reformatting and reshaping the skin. Many probiotics, nutritional supplements, metal nanoparticles, composites, skin constructs, polymers, and so forth have been associated with the improved healing process of wounds. The exact mechanism of material-cellular interaction is a point of immense importance, particularly in pathological conditions such as diabetes. Bioengineered alternative agents will likely continue to dominate the outpatient and perioperative management of chronic, recalcitrant wounds as new products continue to cut costs and improve the wound healing process. This review article provides an update on the various remedies with confirmed wound healing activities of metal-based nanoceutical adjuvanted agents and also other nano-based counterparts from previous experiments conducted by various researchers.

Peripheral neuropathy induced by drinking water contaminated with low-dose arsenic in Myanmar.

BACKGROUND: More than 140 million people drink arsenic-contaminated groundwater. It is unknown how much arsenic exposure is necessary to cause neurological impairment. Here, we evaluate the relationship between neurological impairments and the arsenic concentration in drinking water (ACDW). PARTICIPANTS AND METHODS: A cross-sectional study design was employed. We performed medical examinations of 1867 residents in seven villages in the Thabaung township in Myanmar. Medical examinations consisted of interviews regarding subjective neurological symptoms and objective neurological examinations of sensory disturbances. For subjective neurological symptoms, we ascertained the presence or absence of defects in smell, vision, taste, and hearing; the feeling of weakness; and chronic numbness or pain. For objective sensory disturbances, we examined defects in pain sensation, vibration sensation, and two-point discrimination. We analyzed the relationship between the subjective symptoms, objective sensory disturbances, and ACDW. RESULTS: Residents with ACDW ≥ 10 parts per billion (ppb) had experienced a "feeling of weakness" and "chronic numbness or pain" significantly more often than those with ACDW < 10 ppb. Residents with ACDW ≥ 50 ppb had three types of sensory disturbances significantly more often than those with ACDW < 50 ppb. In children, there was no significant association between symptoms or signs and ACDW. CONCLUSION: Subjective symptoms, probably due to peripheral neuropathy, occurred at very low ACDW (around 10 ppb). Objective peripheral nerve disturbances of both small and large fibers occurred at low ACDW (> 50 ppb). These data suggest a threshold for the occurrence of peripheral neuropathy due to arsenic exposure, and indicate that the arsenic concentration in drinking water should be less than 10 ppb to ensure human health.

Deciphering the molecular events during arsenic induced transcription signal cascade activation in cellular milieu.

Anthropogenic sources of arsenic poses and creates unintentional toxico-pathological concerns to humans in many parts of the world. The understanding of toxicity of this metalloid, which shares properties of both metal and non-metal is principally structured on speciation types and holy grail of toxicity prevention. Visible symptoms of arsenic toxicity include nausea, vomiting, diarrhea and abdominal pain. In this review, we focused on the dermal cell stress caused by trivalent arsenic trioxide and pentavalent arsanilic acid. Deciphering the molecular events involved during arsenic toxicity and signaling cascade interaction is key in arsenicosis prevention. FoxO1 and FoxO2 transcription factors, members of the Forkhead/Fox family, play important roles in this aspect. Like Foxo family proteins, ATM/CHK signaling junction also plays important role in DNA nuclear factor guided cellular development. This review will summarize and discuss current knowledge about the interplay of these pathways in arsenic induced dermal pathogenesis.

Hemoglobin stimulates the expression of ADAMTS-5 and ADAMTS-9 by synovial cells: a possible cause of articular cartilage damage after intra-articular hemorrhage.

BACKGROUND: ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) proteins play an important pathological role in matrix degeneration. Aggrecan degradation is a significant and critical event in early-stage osteoarthritis. To determine the effect of hemoglobin (Hb) on the ability of synovial tissues to produce ADAMTS family members, we examined the influence of Hb by synovial cells in an in vitro experimental system. METHODS: Synovial tissues were obtained from five young patients with meniscal injury under arthroscopic surgery. Primary cultures of human knee synovial cells were treated with different doses of human Hb (0, 25, 50, 100 µg/ml). The culture media were collected 24 h after Hb-treatment. In the time-course studies, cells were treated with and without 100 µg/ml Hb, and culture media were taken at 6, 12, and 24 h. To identify the proteins responsible for aggrecanase activity, Western blot analysis using antibodies against human ADAMTS-5, -8, -9, and -10; enzyme-linked immunosorbent assay (ELISA); and gene expression for ADAMTS-5 and -9 were examined. Statistical comparisons between each group were performed using paired t-tests. RESULTS: Western blot analysis revealed that Hb-treatment resulted in the expression of ADAMTS-5 and -9. Neither control group nor Hb-treated medium showed immunoreactivity against ADAMTS-8 or -10. In a dose-dependency study, the Hb-treated group showed significantly higher levels of ADAMTS-5 and -9 compared with the control (p < 0.05). There was no significant difference between 25, 50, and 100 µg/ml Hb-treated groups. In a time-course study, the ADAMTS-5 and -9 levels in the conditioned medium had significantly increased expression at 6, 12, and 24 h in the Hb-treated group (p < 0.05). Hb evoked significant expression of ADAMTS-9 mRNA at 12 and 24 h (p < 0.05). CONCLUSIONS: These findings indicate that Hb induces the expression of ADAMTS-5 and -9 by synovial cells at low doses, even at an acute phase, and suggests a possible role for Hb in cartilage damage after intra-articular hemorrhage. The results also suggest a new potential therapeutic target by inhibiting the activities of ADAMTS-5 and -9 to prevent cartilage damage after intra-articular hemorrhage.

NFkappaB activation is essential for miR-21 induction by TGFß1 in high glucose conditions.

Transforming growth factor beta1 (TGFß1) is a pleiotropic growth factor with a very broad spectrum of effects on wound healing. Chronic non-healing wounds such as diabetic foot ulcers express reduced levels of TGFß1. On the other hand, our previous studies have shown that the microRNA miR-21 is differentially regulated in diabetic wounds and that it promotes migration of fibroblast cells. Although interplay between TGFß1 and miR-21 are studied in relation to cancer, their interaction in the context of chronic wounds has not yet been investigated. In this study, we examined if TGFß1 could stimulate miR-21 in fibroblasts that are subjected to high glucose environment. MiR-21 was, in fact, induced by TGFß1 in high glucose conditions. The induction by TGFß1 was dependent on NFκB activation and subsequent ROS generation. TGFß1 was instrumental in degrading the NFκB inhibitor IκBα and facilitating the nuclear translocation of NFκB p65 subunit. EMSA studies showed enhanced DNA binding activity of NFκB in the presence of TGFß1. ChIP assay revealed binding of p65 to miR-21 promoter. NFκB activation was also required for the nuclear translocation of Smad 4 protein and subsequent direct interaction of Smad proteins with primary miR-21 as revealed by RNA-IP studies. Our results show that manipulation of TGFß1-NFκB-miR-21 pathway could serve as an innovative approach towards therapeutics to heal diabetic ulcers.

Regulation of growth factors-associated cell migration by C-phycocyanin scaffold in dermal wound healing.

1. The present study examined the role of C-phycocyanin (C-pc) in relation to growth factors and cell migration during wound healing. 2. Histological and biochemical studies showed that C-pc scaffold significantly (P < 0.01) increased hydroxyl proline, total hexamine and protein content, and decreased uronic acid content in the wound tissues during a time course study in newly formed skin. 3. Reverse transcription polymerase chain reaction array of mouse growth factors in wound tissue showed overexpression (up to 10-fold) of growth factors, such as Cxcl12, Fgf18, Lefty 1, Lefty 2, Rabep 1 and Zip91, and downregulation (up to -10-fold) of Amh, Bmp 7 and Nodal genes in a 6-day period in C-pc treated groups. Also, Csf 3, Fgf 22, Mdk, Igf 2, transforming growth factor (TGF)-α 1 and interleukin (IL)-1ß showed an upregulation of more than 30-fold than the control groups. TGF-ß subfamily cytokine growth factors, such as Bmp 2, 4 and 8b, and other growth factors, such as Cxcl 1, showed the highest activity on day 3, showing a transient type of regulation. Western blot analysis showed a positive correlation between gene activity and protein expressions of Bmp 8b, Bmp4, Bmp2 and Cxcl 1. Day 6 in the C-pc group showed the highest csf3 and IL-1ß expression. 4. C-pc had no direct effect on keratinocyte migration. However, keratinocytes that were co-cultured with fibroblasts showed a significantly higher rate of migration in the presence of C-pc, showing an indirect effect of C-pc on keratinocyte migration. 5. In conclusion, biodegradable C-pc scaffold might help to serve as an alternate scaffold material for wound healing.

Exploring the Pattern of Metabolic Alterations Causing Energy Imbalance via PPARα Dysregulation in Cardiac Muscle During Doxorubicin Treatment.

Cardiotoxicity by anthracycline antineoplastic drug doxorubicin is one of the systemic toxicity of the cardiovascular system. The mechanism responsible for doxorubicin cardiotoxicity and lipid metabolism remains elusive. The current study tested the hypotheses that the role of peroxisome proliferator-activated receptor α (PPARα) in the progress of doxorubicin-induced cardiomyopathy and its mechanism behind lipid metabolism. In the present study, male rats were subjected to intraperitoneal injection (5-week period) of doxorubicin with different dosages such as low dosage (1.5 mg/kg body weight) and high dosage (15 mg/kg body weight) to induce doxorubicin cardiomyopathy. Myocardial PPARα was impaired in both low dosage and high dosage of doxorubicin-treated rats in a dose-dependent manner. The attenuated level of PPARα impairs the expression of the genes involved in mitochondrial transporter, fatty acid transportation, lipolysis, lipid metabolism, and fatty acid oxidation. Moreover, it disturbs the reverse triacylglycerol transporter apolipoprotein B-100 (APOB) in the myocardium. Doxorubicin elevates the circulatory lipid profile and glucose. Further aggravated lipid profile in circulation impedes the metabolism of lipid in cardiac tissue, which causes a lipotoxic condition in the heart and subsequently associated disease for the period of doxorubicin treatment. Elevated lipids in the circulation translocate into the heart dysregulates lipid metabolism in the heart, which causes augmented oxidative stress and necro-apoptosis and mediates lipotoxic conditions. This finding determines the mechanistic role of doxorubicin-disturbed lipid metabolism via PPARα, which leads to cardiac dysfunction.

Retinoic acid attenuates nuclear factor kappaB mediated induction of NLRP3 inflammasome.

BACKGROUND: Acetylcholine (ACh), a neurotransmitter and a part of the cholinergic system, can modify immune responses. Expression of acetylcholine receptors (AChR) in immune cells, including macrophages, leads to modulation of their function. Inflammasomes are part of the innate immune system and have been linked to a variety of inflammatory diseases. The NLRP3/ASC/caspase-1/IL-1 axis has emerged as a critical signaling pathway in inflammation process initiation. The role of ACh in modulating inflammasomes in macrophages remains relatively under-explored. METHODS: The effect of AChR agonist carbachol on inflammasome expression was investigated using murine and human macrophages. Cell lysates were assessed by western blot for protein analysis. Immunofluorescence studies were used to study the translocation of p65. The experiments were conducted in the presence of NF-ĸB inhibitor, AChR antagonists, and retinoic acid (RA) to study the role of NF-ĸB, ACh receptors, and RA, respectively. RESULTS: We found that carbachol increased the expression of NLRP3 inflammasome (NLRP3, ASC, cleaved caspase-1, IL-1ß, and IL-18). The treated cells also showed an increase in NF-ĸB activation. The effect of carbachol was diminished by NF-ĸB inhibitor and atropine, a mAChR antagonist. The addition of RA also significantly reduced the effect of carbachol on NLRP3 inflammasomes. CONCLUSIONS: Our current study suggests that carbachol induces NLRP3 inflammasome activation through mAChR and NF-ĸB, and that RA abolishes the inflammatory response. It reveals the potentials of co-administration of RA with cholinergic drugs to prevent inflammatory responses during cholinergic medications.

Effect of coffee extracts on plasma fibrinolysis and platelet aggregation.

We have previously reported on study results showing that certain types of coffee have the activity to enhance fibrinolysis. This report covers the activity of 10 types of hot water extracts of coffee on human tissue-type plasminogen activator producing cells. Particularly strong activity (29-35 times the control amount) was observed for Blue Mountain, Yunnan and Kilimanjaro beans. It was found that the hot water extracts have anti-thrombin activity, and that coffee components have anti-platelet aggregation activity, although weak. It was revealed that there is no activity affecting tissue-type plasminogen activator producing cells in the coffee components chlorogenic acid, caffeine, quinic acid, trigonelline hydrochloride, 5-(hydroxymethyl)-2-furfuryl and caffeic acid. It was also revealed that there is activity in fractions with a molecular weight of 10,000 or less. This could also be inferred from the fact that oral administration of such fractions of coffee to human subjects resulted in a shortening of their plasma ELT (p<0.05).

MicroRNA 21 Elicits a Pro-inflammatory Response in Macrophages, with Exosomes Functioning as Delivery Vehicles.

MicroRNAs can regulate inflammatory responses by modulating macrophage polarization. Although microRNA miR-21 is linked to crucial processes involved in inflammatory responses, its precise role in macrophage polarization is controversial. In this study, we investigated the functional relevance of endogenous miRNA-21 and the role of exosomes. RAW 264.7 macrophages were transfected with miR-21 plasmid, and the inflammatory response was evaluated by flow cytometry, phagocytosis, and real-time PCR analysis of inflammatory cytokines. To understand the signaling pathways' role, the cells were treated with inhibitors specific for PI3K or NFĸB. Exosomes from transfected cells were used to study the paracrine action of miR-21 on naive macrophages. Overexpression of miR-21 resulted in significant upregulation of pro-inflammatory cytokines, pushing the cells towards a pro-inflammatory phenotype, with partial involvement of PI3K and NFĸB signal pathways. The cells also secreted miR-21 rich exosomes, which, on delivery to naive macrophages, caused them to exhibit pro-inflammatory activity. The presence of miR-21 inhibitor quenched the inflammatory response. This study validates the pro-inflammatory property of miR-21 with a tendency to foster an inflammatory milieu. Our findings also reinforce the dual importance of exosomal miR-21 as a biomarker and therapeutic target in inflammatory conditions.

An appraisal on molecular and biochemical signalling cascades during arsenic-induced hepatotoxicity.

Arsenic is a ubiquitous metalloid compound commonly found in the environment, and it is usually found in combination with sulphur and metals. Arsenic is considered as a therapeutic as well as poisoning agent since ancient times. It causes toxic effects on different organs, mainly the liver. In this review, we focused on the molecular mechanism of arsenic-induced hepatotoxicity. Here we envisaged the bridge between arsenic and hepatotoxicity with particular focus on the level of hepatic enzymes such as ALT, AST, and ALP. Here, we attempted to elucidate the role of arsenic in redox imbalance on increased oxidative stress (elevated level of ROS, MDA and NO) and decreased antioxidant levels such as reduced GSH, catalase, and SOD. Oxidative stress induces mitochondrial dysfunction via apoptosis (AKT-PKB, MAPK, PI3/AKT, PKCδ-JNK, AKT/ERK, p53 pathways), fibrosis (TGF-ß/Smad pathway), and necrosis and inflammation (TNF-α, NF-ĸB, IL-1, and IL-6). Along with that, arsenic activates caspases and Bax, decreases Bcl2 through mitochondrial dysfunction, and induces apoptosis regulatory mechanism. We believe the alteration of all these pathways leads to arsenic-induced hepatotoxicity.

c-Phycocyanin primed silver nano conjugates: Studies on red blood cell stress resilience mechanism.

Green synthesis of metal-encased nutraceutical nano-hybrids has been a target for research over the last few years. In the present investigation, we have reported temperature dependent facile synthesis of silver nanoparticles using FDA approved c phycocyanin (cPC). The cPC conjugated silver nanoparticles (AgcPCNPs) were characterized by TEM, Zeta Potential, UV-vis, XPS, FTIR, and CD Spectroscopy. The temperature optimization studies suggested the synthesis of stable AgcPCNPs at 40 °C while at higher temperature system shows aggregated appearance. Molecular docking studies predicted the exclusive interaction of C, D, I, and J chains of cPC with the surface of AgNPs. Moreover, AgcPCNPs significantly (p < 0.1 %) counteract the toxic nature of AgNPs on red blood cell by measuring parameters like total RBC count, % hemolysis, % hematocrit, coagulation time, pH, electrolyte concentrations and degree of blood cell lipid peroxidation by the anti-oxidation mechanism. Skin fibroblast in vitro cell migration result suggeststhat AgcPCNPs enhanced the degree of cell movement towards the wound area. Data obtained collectively demonstrate that AgcPCNPs can be a better agent in the dermal wound healing with reduced toxicity with the bi-phasic advantage of cPC as a wound healer and Ag nano-metal as an anti-bacterial agent.

The pivotal role of microRNA-21 in osteoclastogenesis inhibition by anthracycline glycoside aloin.

Osteopenic disorders such as osteoporosis and rheumatoid arthritis are characterized by excessive bone resorption by osteoclasts relative to bone formation by osteoblasts. MicroRNAs are emerging as key players in bone remodeling, modulating the functions of both osteoblasts and osteoclasts. Among them, miR-21 is highly expressed in osteoclast precursors and is known to regulate genesis, differentiation, and apoptosis of osteoclasts. The pro-osteoclastogenic nature of miR-21 makes it a potential candidate as a therapeutic target to treat bone disorders. We had previously demonstrated that anthroglycoside aloin derived from Aloe vera was effective in promoting osteoblastogenesis and inhibiting osteoclastogenesis. The present study investigated the role of miR-21 in aloin's inhibitory effect on osteoclast differentiation. Aloin effectively suppressed receptor activator of nuclear factor kappa-B (NFĸB) ligand (RankL)-induced miR-21 expression via repression of NFĸB activation. MiR-21 suppression resulted in upregulation of osteoclast suppressor programmed cell death protein 4 (PDCD4), and downregulation of osteoclast marker cathepsin K. Knockdown or gain-of-function studies revealed that miR-21 was pivotal to aloin's inhibitory effect on osteoclastogenesis. This study also highlights the dynamic potential of aloin as a therapeutic agent to treat osteopenic disorders.

An appraisal of cuticular wax of Calotropis procera (Ait.) R. Br.: Extraction, chemical composition, biosafety and application.

Plastic and polythene as hydrophobic materials become a grave concern due to their non-biodegradable nature, cumbersome recycling and waste management. Cuticular wax derived from Calotropis procera is explored as an eco-friendly and safe hydrophobic material. The effects of duration of exposure to solvent, solvent type, size and side of the leaf on cuticular wax yield have been studied. Leaf with the smallest area (10 cm2-25 cm2) was found to be the most suitable to isolate the wax. GC-MS analysis of the wax revealed that the wax consists of mainly esters, alkane and alkene. Mitochondrial reductase (MTT) and lactate dehydrogenase (LDH) assay have been carried out on M5S cell line at various concentrations and the results indicate that up to 1 µg/ml (acetone as solvent) and 3 µg/ml (chloroform as solvent) use of wax has no toxic effect. To evaluate the hydrophobic potential of the wax in developing hydrophobic paper water regains and contact angle has been measured. The gain in hydrophobicity of the paper is evident from the rise in contact angle (≥90˚) of paper coated with wax. Scanning electron micrograph and FTIR spectra generated physical and chemical evidence of coating of wax on paper.

Single step formation of biocompatible bimetallic alloy nanoparticles of gold and silver using isonicotinylhydrazide.

Manufacturing nanoparticles with controlled physicochemical properties using environment-friendly routes have potential to open new prospects for a variety of applications. Accordingly, several approaches have been established for manufacturing metal nanoparticles. Many of these approaches entail the use of hazardous chemicals and could be toxic to the environment, and cannot be used readily for biomedical applications. In the present work, we report a single step bio-friendly approach to formulate gold (Au), silver (Ag), and Au-Ag alloy nanoparticles with desired surface corona and composition using isonicotinylhydrazide (INH) as a reducing agent. INH also functioned as a stabilizing agent by enabling a surface corona around the nanoparticles. Remarkably, within a single step INH could also provide a handle in regulating the composition of Au and Ag in bimetallic systems without any additional chemical modification. The physicochemical and surface properties of the different nanoparticles thus obtained have been examined by analytical, spectroscopic and microscopic techniques. Cell cytotoxicity (release of lactate dehydrogenase), cell viability and intracellular reactive oxygen species (ROS) assays confirmed that the Au, Ag, and Au-Ag bimetallic nanoparticles prepared with INH are biocompatible. Finally, the presence of organic surface corona of INH on the nanoparticles was found to impart nanozyme activity and antimycobacterial sensitivity to the nanoparticles.

Nattokinase-promoted tissue plasminogen activator release from human cells.

When heated to a temperature of 70 degrees C or higher, the strong fibrinolytic activity of nattokinase in a solution was deactivated. Similar results were observed in the case of using Suc-Ala-Ala-Pro-Phe-pNA and H-D-Val-Leu-Lys-pNA, which are synthetic substrates of nattokinase. In the current study, tests were conducted on the indirect fibrinolytic effects of the substances containing nattokinase that had been deactivated through heating at 121 degrees C for 15 min. Bacillus subtilis natto culture solutions made from three types of bacteria strain were heat-treated and deactivated, and it was found that these culture solutions had the ability to generate tissue plasminogen activators (tPA) from vascular endothelial cells and HeLa cells at certain concentration levels. For example, it was found that the addition of heat-treated culture solution of the Naruse strain (undiluted solution) raises the tPA activity of HeLa cells to about 20 times that of the control. Under the same conditions, tPA activity was raised to a level about 5 times higher for human vascular endothelial cells (HUVEC), and to a level about 24 times higher for nattokinase sold on the market. No change in cell count was observed for HeLa cells and HUVEC in the culture solution at these concentrations, and the level of activity was found to vary with concentration.

Porcine skeletal muscle troponin is a good source of peptides with Angiotensin-I converting enzyme inhibitory activity and antihypertensive effects in spontaneously hypertensive rats.

In the search for novel peptides that inhibit the angiotensin I-converting enzyme (ACE), porcine skeletal troponin was hydrolyzed with pepsin, and the products were subjected to various types of chromatography to isolate active peptides. Glu-Lys-Glu-Arg-Glu-Arg-Gln (EKERERQ) and Lys-Arg-Gln-Lys-Tyr-Asp-Ile (KRQKYDI) were identified as active peptides, and their 50% inhibitory concentrations were found to be 552.5 and 26.2 microM, respectively. These are novel ACE inhibitory peptides, and the activity of KRQKYDI was the strongest among previously reported troponin-originated peptides. KRQKYDI was slowly hydrolyzed by treatment with ACE, and kinetic studies indicated that this peptide was a competitive inhibitor of the enzyme. When KRQKYDI was administered orally to spontaneously hypertensive rats (SHR) at a dose of 10 mg/kg, a temporary antihypertensive activity was observed at 3 and 6 h after administration.

Review on molecular and biochemical insights of arsenic-mediated male reproductive toxicity.

Arsenic is a natural metalloid found in abundance, in the environment. Exposure to arsenic can cause health issues due to its carcinogenic nature. The primary source of arsenic contact is drinking water. Exposure to arsenic in drinking water can cause reproductive dysfunction in males through a reduction in testes weight, accessory sex organ weight, viability, and motility of sperm, epididymal sperm count, decreased gonadotrophins level, decreased testosterone, and steroidogenesis disruption. This review focuses on the mechanisms by which arsenic impairs the quality of semen, based on epidemiological observations in humans, and experimental studies in different biological research models. Arsenic-mediated male reproductive toxicity can be induced by various mechanisms such as inhibition of spermatogenesis, testosterone pathway hinderance, oxidative stress, inflammation, genotoxic effects, activation of heat shock proteins, and activation of a signaling pathway in testes (ERK/AKT/NF-kB signaling pathway), among others. The interplay between the principal mechanisms involved needs to be elucidated further in future since an overall examination of arsenic-mediated male reproductive toxicity is still a deficit.