Effects of High-Intensity, Eccentric-Only Muscle Actions on Serum Biomarkers of Collagen Degradation and Synthesis.

ABSTRACT: Neltner, TJ, Sahoo, PK, Smith, RW, Anders, JPV, Arnett, JE, Ortega, DG, Schmidt, RJ, Johnson, GO, Natarajan, SK, and Housh, TJ. Effects of high-intensity, eccentric-only muscle actions on serum biomarkers of collagen degradation and synthesis. J Strength Cond Res 37(9): 1729-1737, 2023-The purpose of this study was to examine the effects of high-intensity, eccentric-only muscle actions of the leg extensors on (a) serum biomarkers of collagen degradation (hydroxyproline [HYP] and C-terminal telopeptide of type I collagen [C1M]) and synthesis (pro-c1α1) and (b) the time course of changes in maximal voluntary isometric contraction (MVIC) and ratings of muscle soreness after the eccentric-only exercise bout. Twenty-five recreationally active men (mean ± SD: age = 21.2 ± 2.0 years) completed 5 sets of 10 bilateral, eccentric-only dynamic constant external resistance muscle actions of the leg extensors at a load of 110% of their concentric leg extension 1 repetition maximum. Analysis of variances (p < 0.05) and a priori planned pairwise comparisons using Bonferroni corrected (p < 0.0167) paired t tests were used to examine mean changes in blood biomarkers from baseline to 48 hours postexercise as well as in MVIC and soreness ratings immediately, 24 hours, and 48 hours postexercise. There were increases in HYP (3.41 ± 2.37 to 12.37 ± 8.11 µg·ml-1; p < 0.001) and C1M (2.50 ± 1.05 to 5.64 ± 4.89 µg·L-1; p = 0.003) from preexercise to 48 hours postexercise, but no change in pro-c1α1. Maximal voluntary isometric contraction declined immediately after the exercise bout (450.44 ± 72.80 to 424.48 ± 66.67 N·m; p = 0.002) but recovered 24 hours later, whereas soreness was elevated immediately (6.56 ± 1.58; p < 0.001), 24 hours (3.52 ± 1.53; p < 0.001), and 48 hours (2.60 ± 1.32; p = 0.001) postexercise. The eccentric-only exercise bout induced increases in collagen degradation but had no effect on collagen synthesis. These findings provide information for clinicians to consider when prescribing exercise after an acute injury or surgery.

Viral characteristics and clinical presentation in dengue co-infection- Findings from a facility based observational study in Odisha, India.

BACKGROUND: Dengue has affected many countries globally. Two-fifths part of the world is at risk, which can be affected by dengue disease. In India, the dengue incidence has increased in the recent past and emerged as an important health problem in many states including Odisha. Dengue disease presents with atypical clinical symptoms when associated with other co-infections. MATERIALS AND METHODS: A facility-based longitudinal study was carried out over a period of 1 year to determine the dengue co-infection and its outcome. The suspected cases were clinically assessed following a standard case report format and serological investigations including serotyping were carried out. RESULTS: 33.6% samples were dengue positive of which 78.5% were positive for NS1 Ag, 26.6% positive for dengue IgM and 5.1% to both. Among the dengue positive cases, 60.9% were male and mean age was 31.52 (±17.03) years. High occurrence of cases was during May to November with maximum in August. Among the 975 dengue positives, 57 (5.8%) were found to have co-infection. Chikungunya was the most common co-infection in 71.9%, followed by herpes simplex (HSV) (7%) and other diseases. Fever was the most common presenting symptom (98.2%), followed by myalgia (91.2%), retro orbital pain (91.2%), pain abdomen (12.3%), rash/lesion (8.8%), burning micturition (5.3%), petechiae (1.7%) and pruritus (1.7%) among the co-infected cases. CONCLUSIONS: All the four dengue serotypes were found to be circulating with DEN 2 as the most predominant one. About 5.8% of dengue cases have co-infection (mainly with Chikungunya) and clinically present with atypical signs and symptoms.

Palmitoleate Protects against Zika Virus-Induced Placental Trophoblast Apoptosis.

Zika virus (ZIKV) infection in pregnancy is associated with the development of microcephaly, intrauterine growth restriction, and ocular damage in the fetus. ZIKV infection of the placenta plays a crucial role in the vertical transmission from the maternal circulation to the fetus. Our previous study suggested that ZIKV induces endoplasmic reticulum (ER) stress and apoptosis of placental trophoblasts. Here, we showed that palmitoleate, an omega-7 monounsaturated fatty acid, prevents ZIKV-induced ER stress and apoptosis in placental trophoblasts. Human trophoblast cell lines (JEG-3 and JAR) and normal immortalized trophoblasts (HTR-8) were used. We observed that ZIKV infection of the trophoblasts resulted in apoptosis and treatment of palmitoleate to ZIKV-infected cells significantly prevented apoptosis. However, palmitate (saturated fatty acid) did not offer protection from ZIKV-induced ER stress and apoptosis. We also observed that the Zika viral RNA copies were decreased, and the cell viability improved in ZIKV-infected cells treated with palmitoleate as compared to the infected cells without palmitoleate treatment. Further, palmitoleate was shown to protect against ZIKV-induced upregulation of ER stress markers, C/EBP homologous protein and X-box binding protein-1 splicing in placental trophoblasts. In conclusion, our studies suggest that palmitoleate protects placental trophoblasts against ZIKV-induced ER stress and apoptosis.

Saturated free fatty acids induce placental trophoblast lipoapoptosis.

INTRODUCTION: Obesity during pregnancy increases the risk for maternal complications like gestational diabetes, preeclampsia, and maternal inflammation. Maternal obesity also increases the risk of childhood obesity, intrauterine growth restriction (IUGR) and diabetes to the offspring. Increased circulating free fatty acids (FFAs) in obesity due to adipose tissue lipolysis induces lipoapoptosis to hepatocytes, cholangiocytes, and pancreatic-ß-cells. During the third trimester of human pregnancy, there is an increase in maternal lipolysis and release of FFAs into the circulation. It is currently unknown if increased FFAs during gestation as a result of maternal obesity cause placental cell lipoapoptosis. Increased exposure of FFAs during maternal obesity has been shown to result in placental lipotoxicity. The objective of the present study is to determine saturated FFA-induced trophoblast lipoapoptosis and also to test the protective role of monounsaturated fatty acids against FFA-induced trophoblast lipoapoptosis using in vitro cell culture model. Here, we hypothesize that saturated FFAs induce placental trophoblast lipoapoptosis, which was prevented by monounsaturated fatty acids. METHODS: Biochemical and structural markers of apoptosis by characteristic nuclear morphological changes with DAPI staining, and caspase 3/7 activity was assessed. Cleaved PARP and cleaved caspase 3 were examined by western blot analysis. RESULTS: Treatment of trophoblast cell lines, JEG-3 and JAR cells with palmitate (PA) or stearate (SA) induces trophoblast lipoapoptosis as evidenced by a significant increase in apoptotic nuclear morphological changes and caspase 3/7 activity. We observed that saturated FFAs caused a concentration-dependent increase in placental trophoblast lipoapoptosis. We also observed that monounsaturated fatty acids like palmitoleate and oleate mitigates placental trophoblast lipoapoptosis caused due to PA exposure. CONCLUSION: We show that saturated FFAs induce trophoblast lipoapoptosis. Co-treatment of monounsaturated fatty acids like palmitoleate and oleate protects against FFA-induced trophoblast lipoapoptosis.

Zika virus infection induces endoplasmic reticulum stress and apoptosis in placental trophoblasts.

Zika virus (ZIKV) infection to a pregnant woman can be vertically transmitted to the fetus via the placenta leading to Congenital Zika syndrome. This is characterized by microcephaly, retinal defects, and intrauterine growth retardation. ZIKV induces placental trophoblast apoptosis leading to severe abnormalities in the growth and development of the fetus. However, the molecular mechanism behind ZIKV-induced apoptosis in placental trophoblasts remains unclear. We hypothesize that ZIKV infection induces endoplasmic reticulum (ER) stress in the trophoblasts, and sustained ER stress results in apoptosis. HTR-8 (HTR-8/SVneo), a human normal immortalized trophoblast cell and human choriocarcinoma-derived cell lines (JEG-3 and JAR) were infected with ZIKV. Biochemical and structural markers of apoptosis like caspase 3/7 activity and percent apoptotic nuclear morphological changes, respectively were assessed. ZIKV infection in placental trophoblasts showed an increase in the levels of CHOP mRNA and protein expression, which is an inducer of apoptosis. Next, we also observed increased levels of ER stress markers such as phosphorylated forms of inositol-requiring transmembrane kinase/endoribonuclease 1α (P-IRE1α), and its downstream target, the spliced form of XBP1 mRNA, phosphorylated eukaryotic initiation factor 2α (P-eIF2α), and activation of cJun N-terminal Kinase (JNK) and p38 mitogen activated protein kinase (MAPK) after 16-24 h of ZIKV infection in trophoblasts. Inhibition of JNK or pan-caspases using small molecule inhibitors significantly prevented ZIKV-induced apoptosis in trophoblasts. Further, JNK inhibition also reduced XBP1 mRNA splicing and viral E protein staining in ZIKV infected cells. In conclusion, the mechanism of ZIKV-induced placental trophoblast apoptosis involves the activation of ER stress and JNK activation, and the inhibition of JNK dramatically prevents ZIKV-induced trophoblast apoptosis.

Omega-3 Fatty Acid-Derived Resolvin D2 Regulates Human Placental Vascular Smooth Muscle and Extravillous Trophoblast Activities.

Omega-3 fatty acids are important to pregnancy and neonatal development and health. One mechanism by which omega-3 fatty acids exert their protective effects is through serving as substrates for the generation of specialized pro-resolving lipid mediators (SPM) that potently limit and resolve inflammatory processes. We recently identified that SPM levels are increased in maternal blood at delivery as compared to umbilical cord blood, suggesting the placenta as a potential site of action for maternal SPM. To explore this hypothesis, we obtained human placental samples and stained for the SPM resolvin D2 (RvD2) receptor GPR18 via immunohistochemistry. In so doing, we identified GPR18 expression in placental vascular smooth muscle and extravillous trophoblasts of the placental tissues. Using in vitro culturing, we confirmed expression of GPR18 in these cell types and further identified that stimulation with RvD2 led to significantly altered responsiveness (cytoskeletal changes and pro-inflammatory cytokine production) to lipopolysaccharide inflammatory stimulation in human umbilical artery smooth muscle cells and placental trophoblasts. Taken together, these findings establish a role for SPM actions in human placental tissue.

Decreased prevalence of sepsis but not mild or severe P. falciparum malaria is associated with pre-existing filarial infection.

BACKGROUND: Enhanced inflammatory host responses have been attributed as the cellular basis for development of severe malaria as well as sepsis. In contrast to this, filarial infections have been consistently reported to be associated with an immunological hypo-responsive phenotype. This suggests that successful control of filariasis by employing mass drug administration, could potentially contribute to an increase in incidence of sepsis and cerebral malaria in human communities. A case control study was undertaken to address this critical and urgent issue. METHODS: Eighty-nine patients with sepsis and one hundred and ninety-six patients with P. falciparum malaria all originating from Odisha, were tested for prevalence of circulating filarial antigens - a quantitative marker of active filarial infection. Antibodies to four stage specific malarial recombinant proteins were measured by solid phase immunoassays and circulating CD4+CD25high T-cells were quantified by flow cytometry with an objective to study if pre-existing filarial infections influence antibody responses to malarial antigens or the levels of circulating T-regulatory cells in P. falciparum infected patients. RESULTS: Prevalence of filarial antigenemia was significantly less in sepsis patients as compared to controls suggesting that pre-existing filariasis could influence development of sepsis. On the other hand, levels of circulating filarial antigen were comparable in severe malaria cases and healthy controls suggesting that development of severe malaria is independent of pre-existing W. bancrofti infections. Plasma TNF-a, RANTES and antibodies to recombinant malarial proteins as well as levels of circulating CD4+ CD25high cells were comparable in malaria patients with or without filarial infections. CONCLUSIONS: These observations imply that successful control of filariasis could have adverse consequences on public health by increasing the incidence of sepsis, while the incidence of severe malaria may not adversely increase as a consequence of elimination of filariasis.

Association of TNF level with production of circulating cellular microparticles during clinical manifestation of human cerebral malaria.

Microparticles (MPs) resulting from vesiculation of different cell types in Plasmodium falciparum infection correlate with the level of proinflammatory cytokine TNF that may thereby determine the disease severity. Using TruCount tube based flow cytometric method for the exact quantification of MP and enzyme linked immunosorbent assay for the measurement of TNF, we conducted a hospital based case control study on P. falciparum malaria patients to scrutinize and infer the link between the two. In 52 cerebral malaria (CM), 21 multi-organ-dysfunction (MOD), 12 non cerebral severe malaria (NCSM) and 43 uncomplicated malaria patients, the MP level was found to be significantly elevated in febrile malaria patients compared to healthy controls and a striking decrease in MP level was observed with the clearance of the P. falciparum infection in the patients upon follow-up. The lowering of the parasite density with the level of plasma TNF and the positive correlation of the cytokine with the cell derived MPs and negative correlation with the respective cell count in human malaria patients suggests that TNF may be a key stimulant to the cells resulting in the release of MPs in malaria infection.

Macrofilaricidal activity and amelioration of lymphatic pathology in bancroftian filariasis after 3 weeks of doxycycline followed by single-dose diethylcarbamazine.

In a placebo controlled trial, the effects of 21- and 10-day doxycycline treatments (200 mg/day) followed by single dose diethylcarbamazine (administered 4 months post treatment) on depletion of Wolbachia endobacteria from Wuchereria bancrofti, filaricidal activity, and amerlioration of scrotal lymph vessel dilation were studied in 57 men from Orissa, India. The 21-day doxycycline course reduced Wolbachia in W. bancrofti by 94% before diethylcarbamazine administration. After 12 months, all patients with this treatment were amicrofilaremic and different from the 10-day doxycycline (42.9%) and placebo (37.5%) groups, and significantly fewer were positive for scrotal worm nests (6.7%) compared with 10-day doxycycline (60%) and placebo (66.7%). Average scrotal lymph vessel diameters were reduced from 0.7 cm pre-treatment to 0.02 cm in patients after 21 days of treatment, while no significant changes were seen in the other groups. This latter feature confirms the beneficial effects of doxycycline on lymphatic dilation and thus adds to the existing evidence that doxycycline, in addition to being macrofilaricidal, may be used to prevent or reverse lymphatic pathology.

Protective immunity in human filariasis: a role for parasite-specific IgA responses.

BACKGROUND: Filaria-specific antibodies of immunoglobulin (Ig) G, IgE, and IgM isotypes have been correlated with acquired immunity in the literature, but the status of filaria-specific IgA and its role in human filariasis has not been addressed. The present study attempts to fill this lacuna. METHODS: Both total and filaria-specific IgA to different developmental stages of filarial parasites were quantified by solid-phase immunoassays in 412 clinically and parasitologically defined cases occurring in an area endemic for human bancroftian filariasis in Orissa, India. RESULTS: Compared with other clinical categories, microfilariae carriers were deficient in total as well as filaria-specific IgA. More crucially, significantly high levels were observed in putatively immune control subjects from areas of endemicity. These associations were also related to sex; female subjects in each category displayed higher levels of filaria-specific IgA than did male subjects. CONCLUSION: The study demonstrates, for the first time, a positive correlation between protective immunity and increased levels of filaria-specific IgA in human bancroftian filariasis. Furthermore, filaria-specific IgA appears to be an immunological window for the sex-related differences in susceptibility to infection observed in human filariasis.

Human bancroftian filariasis: immunological markers of morbidity and infection.

Induction of host cytokines plays a critical role in infection as well as disease in human filariasis. Measurements of such molecules in plasma could be used as windows of markers both for understanding the pathogenesis of the disease and for identifying markers of morbidity. Eight inflammatory and non-inflammatory host molecules in circulation were quantified in 207 subjects in filariasis endemic area of Orissa, India. IL-6, IL-8, IL-10, TNF-alpha, TNFR-I, TNFR-II, LBP and sICAM-1 were quantified by immunoassays and were analyzed by multivariate exploratory data analysis methods followed by multivariate analysis of variance. Raised levels of IL-6 and IL-8 emerged as markers of acute as well as chronic disease, while increased TNF-alpha was a feature found only in acute filariasis. Decreased sICAM-1 was a feature found only in asymptomatic subjects with filarial infection. There was a dichotomy in plasma levels of two TNF receptors between infected subjects and patients with filarial disease. Since plasma levels of these cytokines are often determined by host genetics, studies on cytokine genetic polymorphisms could offer new insights into the relationship between infection and disease in human lymphatic filariasis.

Concomitant parasitism: bancroftian filariasis and intestinal helminths and response to albendazole.

Subjects in an disease-endemic area in Orissa, India concomitantly infected with filariasis and intestinal helminths had significantly lower intensity of filarial infection in comparison with those who were infected only with filariasis. Administration of albendazole resulted in a significant decrease in the prevalence of filarial antigenemia in subjects concomitantly infected with intestinal helminths, but produced little change in this infection measure in subjects infected only with Wuchereria bancrofti. These results indicate that intestinal helminths could play a role in the anti-filarial activity of albendazole, most probably by depressing filarial infection intensity in co-infected individuals. Confirmation of these findings in a larger cohort may yield important new insights regarding the role of using albendazole in the ongoing intervention programs for the control of lymphatic filariasis.

Protective immunity in human lymphatic filariasis: problems and prospects.

Human filariasis caused by lymphatic dwelling nematodes, affecting 120 million persons worldwide, is a major public health problem. Efforts towards development of vaccines for such large tissue-dwelling nematodes depends significantly on identification and demonstration of protective immunity in the exposed population. Immunological studies conducted in human filariasis so far are essentially attempts to establish a correlation of the immune response phenotypes with presence or absence of filarial infections/disease in the host, and the cause-effect relationship between the observed immune responses in the host and protective immunity continues to be conjectural. This short review attempts to clarify the functional definition of protective immunity, problems associated with identification of putatively immune subjects in endemic areas, role of antibodies reactive to surface of microfilariae and larvae stages of filarial parasites and importance of undertaking immunological investigations on a longitudinal basis in different cohorts of subjects presenting with one or the features of infection and/or disease for more accurate delineation of protective immunity in human filariasis.