bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exercise training differentially impacts 13C4‐octanoic acid oxidation in obese individuals with high and low intrahepatic lipid content‐a pilot study
Authors: Winn Nathan C , Lee Nhan , Kanaley Jill A , Rector R. Scott , Parks Elizabeth J , Ibdah Jamal A 
Published: November 2023

The beneficial adaptations to chronic physical activity (PA) reduce the risk of nonalcoholic fatty liver disease (NAFLD) and PA is a first line treatment for patients diagnosed with NAFLD. Accumulating evidence posits that increased utilization of lipid substrates may be one mechanism by which exercise reduces liver fat (LF); nonetheless there is paucity of data regarding the impact of exercise training on fatty acid oxidation (FAO) in individuals with differing levels of hepatic steatosis. Here, we determined whether the level of medium chain FAO is altered in individuals with varying contents of intrahepatic lipid (IHL) in response to exercise training.MethodsObese individuals (n=8, body mass index, 38.5±1.6 kg/m2) with 1H‐MRS‐measured hepatic steatosis underwent baseline and post‐training meal tests (3 h) with labeled 13C4‐octanoic acid to assess FAO. Frequent breath samples were taken and analyzed for 13CO2 enrichment (%). Subjects were stratified into Low‐ (IHL<15%; n=4) and High‐LF (IHL≥15%; n=4) and compared to non‐exercising controls (n=2). Exercise training was performed 4x/wk for 4 wks at 55–80% maximal oxygen consumption for a duration equivalent to ~400 kcal energy expenditure (30–70 min/session).ResultsAt baseline, IHL was greater in High‐LF (27.0±4.3%) compared to both Low‐LF (10.1±1.4%) and controls (5.0±1.8%), P<0.05. Exercise training decreased IHL in High‐LF (−16.7±5.3%; P<0.05) with no statistically‐significant changes in Low‐LF (−11.3±10.1%) or non‐exercising controls (17.3±14.5%), P>0.05. Body weight, body fat percentage, and fat mass were unchanged with exercise training within groups. Baseline 13CO2 area under the curve (AUC) [Control, 9.7±2.0 AU; Low‐LF, 8.4±0.5 AU; High‐LF, 6.7±1.2 AU] and steady‐state (SS) 13CO2 [Control, 4.2±0.8%; Low‐LF, 3.7±0.2%; High‐LF, 2.9±0.5%] were not different among groups (P>0.05). Neither 13CO2 AUC nor SS 13CO2 were changed with exercise training in High‐LF or non‐exercising controls. By contrast, 13CO2 AUC and SS 13CO2 were reduced in Low‐LF by 26.8±5.4% and 22.1±5.9%, respectively (P<0.05). The change in SS 13CO2 was inversely associated with the change in IHL (r=−0.75, P<0.05).ConclusionsExercise‐induced reductions in IHL, without weight loss, were not accompanied by an increase in medium chain FAO in obese individuals with High‐LF, whereas, FAO was decreased in obese individuals with Low‐LF despite no changes in IHL following exercise training. Larger cohort studies are needed to confirm these findings.
eNOS is expressed by primary murine hepatocytes and regulates fatty acid oxidation in vitro
Authors: Sheldon Ryan D. , Morris E. Matthew , Linden Melissa A. , Meers Grace M. , Thyfault John P. , Laughlin M. Harold , Rector R. Scott 
Published: November 2023

INTRODUCTIONWe previously have shown that loss of hepatic endothelial nitric oxide synthase (eNOS) activity is linked to nonalcoholic steatohepatitis (NASH) development and progression. In addition, whole‐body eNOS−/−mice are susceptible to western diet induced hepatic mitochondrial dysfunction and NASH. However, it is unclear whether eNOS is expressed in hepatocytes and, if so, whether hepatocyte specific eNOS plays a role in regulating mitochondrial function. Here we tested the hypothesis that eNOS is expressed by primary hepatocytes and is necessary for normal fatty acid oxidation.METHODSPrimary murine hepatocytes from wild‐type and eNOS−/− mice were isolated using the two‐step collagenase perfusion and digestion method. For siRNA experiments, WT cells were plated with media containing either scrambled or eNOS siRNA and maintained in culture for 48 hours. In a separate set of experiments, primary hepatocytes from WT or eNOS−/− mice were maintained in a collagen matrix for 5 days. On day 4 in culture, cells were placed in media with or without 500 μM free fatty acids (FFA; 250 μM palmitate + 250 μM oleate) for 21 hours and subsequently placed in 1‐14C palmitate (200μM) containing media for 3‐hours and 14CO2 production was measured to indicate complete palmitate oxidation.RESULTSComplete 1‐14C palmitate oxidation was reduced by 30% (p<0.05) in primary hepatocytes from eNOS−/− versus WT mice, and prior exposure to FFA further reduced 1‐14C palmitate oxidation by 19% and 15% in WT and eNOS−/− hepatocytes, respectively. eNOS mRNA and protein were expressed in isolated primary hepatocytes from WT but not eNOS−/−mice and eNOS siRNA knocked down eNOS mRNA expression in WT cells by ~50%. Knockdown of eNOS reduced PGC1α, NQO1, and BNIP3 mRNA expression by 40–50%, suggesting that hepatocellular eNOS is important for normal mitochondrial biogenesis, antioxidative capacity and mitophagy, respectively.CONCLUSIONSThese findings strongly support a hepatocellular specific role for eNOS in the regulation of mitochondrial content and function in vitro. These data suggest that loss of hepatocellular eNOS function in vivo may represent a novel disease mechanism leading to mitochondrial impairments in NASH.Support or Funding InformationSupport: MU Life Sciences Pre‐doctoral Fellowship (RDS), AHA 14POST20110034 (EMM), NIH R01DK088940 (JPT), NIH HL‐36088 (MHL), VHA‐CDA2 IK2BX001299‐01 (RSR).
Modulation of Cerebral Activity Induced by α‐casozepine, a Benzodiazepine‐like Peptide Derived from Bovine Casein
Authors: Benoit Simon , Chaumontet Catherine , Cakir‐Kiefer Céline , Tomé Daniel , Miclo Laurent 
Published: November 2023

The tryptic hydrolysate of bovine αs1‐casein (CH) displays anxiolytic properties highlighted in several animal species and in humans. Unlike benzodiazepines (BZD), the most prescribed anxiolytic drugs, CH shows neither addiction, dependence, sedation nor toxicity. The search for a carrier bioactive molecule within CH led to the α‐casozepine (α‐CZP), a decapeptide which anxiolytic properties were confirmed in rats. Its affinity for the benzodiazepine site of the GABAA receptor has helped getting the α‐CZP closer to the BZD family, despite a much lower affinity than the BZD reference diazepam. The aim of this study was to characterise the changes in the activity of the brain areas involved in the reduction of anxiety after intraperitoneal administration of α‐CZP by labelling neuronal activity in mice brain, in order to characterise its mechanism of action.Swiss mice were fed with a soy‐protein based diet containing no caseins, in order to prevent the presence or potential release of bioactive peptides from these milk proteins. Animals (8 per group) were placed in an anxiety‐producing situation (light‐dark box) 30 minutes after an intraperitoneal injection of α‐CZP (1 mg/kg), diazepam (1 mg/kg) or of the vehicle used to solubilize the molecules. The molecules were then perfused with formalin 1h30 after this stimulus. Brain expression of c‐Fos (a marker of neuronal activity) was measured by automatic counting with immunofluorescence on sagittal and coronal brains sections.The anxiolytic effects of α‐CZP on mice were confirmed using the light‐dark box (significant augmentation of the time spent in the aversive lit box). Immunofluorescence analysis showed a significant lower expression of c‐Fos in the prefrontal cortex (−60%), hippocampus (−40%), nucleus accumbens (−50%) and hypothalamus (−60%) after administration of the α‐CZP compared to the vehicle. The same profiles were observed after diazepam injection. A significant increase in the expression of c‐Fos in the amygdala (+300%), observed only after the administration of α‐CZP, indicates a different mechanism of action compared to diazepam. Results were confirmed on coronal sections.In conclusion, this study showed that an intraperitoneal administration of α‐CZP, a bioactive peptide resulting of a food protein hydrolysis, allows a modulation of neuronal activity in different brain regions involved in the regulation of anxiety and thereby can partly explain the anxiolytic activity of the peptide. A binding of α‐CZP on BZD receptors could explain the diminution of neuronal activity in different brain regions associated with the anxiolytic effects of the peptide. Moreover, a different mechanism of action of that of diazepam could also account for the absence of side effects observed with CH and this could be explained by the differences observed in the amygdala activation.
The effect of wheat peptides on ethanol‐induced gastric mucosal damage in rats
Authors: Yang Xian , Sun Guiju , Wang Shaokang 
Published: November 2023

ObjeciveExcessive alcohol consumption can lead to gastric mucosal damage and the present work was aimed to examine the protective effect of wheat peptides in the model rats with gastric mucosal damage induced by ethanol.MethodsWheat peptides (83, 167 or 333 mg/kg), cimetidine (65 mg/kg), or distilled water were administered daily by gavage for 30 days before the rats were treated with anhydrous ethanol (1mL) and then animals were euthanized 1 h after ethanol ingestion. Histological observations was performed, so were antioxidation effect, anti‐inflammatory action and caspase‐3.ResultsHistological observations showed that ethanol‐induced gastric mucosal damage was attenuated by wheat peptides pretreatment. Wheat peptides remarkably increased the superoxide dismutase (SOD) activity, epidermal growth factor (EGF) and prostaglandinE‐2 (PGE2) levels in serum. The treatment of wheat peptides dramatically decreased the malondialdehyde (MDA), platelet‐activating factor (PAF) and interleukin‐8 (IL‐8) levels in serum. The expression level of caspase‐3 in stomach was significantly decreased in wheat peptides‐treated rats comparing with the model group, however, the expression level of EGFR was markedly increased.ConclusionEthanol‐induced gastric mucosal damage in rats can be prevented by wheat peptides. And the potential mechanism may be associated with enhancement of antioxidation, anti‐inflammatory action and anti‐apoptosis function.Support or Funding InformationThis work was supported by the cooperation project with china national research institute of food & fermentation industries.
Metformin improves ileal epithelial barrier function in interleukin‐10 deficient mice
Authors: Xue Yansong , Zhang Hanying , Yang Guan , Zhu Mei‐Jun 
Published: November 2023

BackgroundAccumulating evidence shows that gut epithelial integrity and barrier function is a central predisposing factor in the pathogenesis of inflammatory bowel disease. The proper intestinal epithelial proliferation and differentiation is crucial for maintaining gut homeostasis and intestinal integrity.ObjectiveTo evaluate the protective role of metformin in ileal epithelial barrier function using interleukin‐10 deficient (IL10KO) mice.ResultsMetformin supplementation had no effect body weight gain and feed intake, but decreased intestinal permeability in IL10KO mice associated with reduced expression of pore forming tight junction protein, claudin 2 and enhanced expression of barrier forming tight junction protein, claudin 3. Histological analysis showed that IL‐10 depletion elongated crypt depth and increased mucosal thickness, resulting in decreased Villi/Crypt ratio, which was restored by metformin supplementation. Consistent with increased crypt depth, proliferation of epithelial cells in IL10KO mice with or without metformin supplementation was enhanced compared to that of WT mice, while metformin supplementation decreased the number of proliferative cells per crypt in IL10KO mice as assayed by Ki67 staining and in vivo BrdU labeling. The density of Paneth cells was increased in metformin treated mice regardless of genotypes, but the Paneth cell density was decreased dramatically in IL10KO mice when compared to those of WT mice regardless of metformin supplementation. Consistently, the density of goblet cells was much lower in the intestinal epithelium of IL10KO mice compared to that of the WT mice, while metformin supplementation increased the goblet cell density in both WT and IL10KO mice.ConclusionOur data demonstrate that metformin supplementation inhibits cell proliferation, promotes secretory cell lineage differentiation and further improves epithelial barrier function in IL10KO mice.Support or Funding InformationR15HD073864
Mast cells promote biliary proliferation and hepatic fibrosis in normal and HDC−/− mice by interacting with cholangiocytes and hepatic stellate cells via TGF‐β1 signaling
Authors: Francis Heather 
Published: November 2023

BackgroundIn normal, homeostatic conditions, cholangiocytes are mitotically dormant, hepatic stellate cells (HSCs) are quiescent and mast cell (MC) numbers are relatively low. Upon injury resulting in hepatic fibrosis, there is an activation of HSCs and the release of pro‐inflammatory factors like TGF‐β1 from proliferating cholangiocytes. MCs infiltrate the liver following injury and promote biliary hyperplasia by releasing factors like histamine. In mice lacking the histidine decarboxylase gene (HDC−/− mice), MCs are morphologically altered and also low in number. We tested the hypothesis that MCs promote fibrosis in normal and HDC−/−mice by increasing HSC activation, cholangiocyte proliferation and TGF‐β1 release.MethodsNormal, wild‐type (WT) mice and HDC−/− mice were injected with 1xPBS or cultured MCs derived from fetal mouse liver (5 × 106) via tail vein delivery. After 6 days, mice were sacrificed and liver blocks, isolated cholangiocytes and serum was obtained. Biliary mass and proliferation was evaluated by immunohistochemistry for CK‐19 and PCNA, respectively, and hepatic fibrosis and collagen deposition was measured by Masson's Trichrome and Fast Green/Sirius Red staining. Real‐time PCR was performed in total liver and isolated cholangiocytes for fibrotic markers, α‐SMA, collagen‐type 1a and fibronectin. HSC activation was measured by immunofluorescence and real‐time PCR in total liver for synaptophysin‐9 (SYP‐9). TGF‐β1 secretion was measured by EIA in serum from all mice and by real‐time PCR in total liver and isolated cholangiocytes. In vitro, cultured HSCs and cholangiocytes were treated with cultured MCs and fibrosis markers and TGF‐β1 expression/secretion was measured.ResultsMC injection increased biliary mass, proliferation and hepatic fibrosis in both WT and HDC−/− mice compared to controls. HSC activation was also enhanced in mice injected with MC compared to controls. TGF‐β1 secretion in serum and gene expression was increased following MC injections in both WT and HDC−/− mice compared to controls. In vitro, co‐culture with MCs increased cholangiocyte and HSC proliferation, activation and fibrotic marker gene expression.ConclusionIn normal conditions, MCs are low in number, however; when the liver is damaged, MCs infiltrate, release profibrotic factors and induce further damage. Our results demonstrate that MCs promote biliary proliferation, HSC activation and hepatic fibrosis in normal and HDC−/−mice via increased TGF‐β1 signaling. MCs are a pro‐proliferative and pro‐fibrogenic component of hepatic fibrosis. Targeting MCs may be a key therapeutic in fibrotic‐related liver pathologies when MC numbers are increased.Support or Funding InformationVA Career Development Award
Cecal Microbiota Dysbiosis and Hepatic Transcriptomic Alterations in Western Diet‐Induced NASH in Juvenile Ossabaw Swine
Authors: Panasevich Matthew R , Linden M A , Meers G M , Kanosky K M , Reubel M , Perfield J W , Booth F W , Ibdah J A , Oerther D B , Rector R S 
Published: November 2023

Pediatric nonalcoholic steatohepatitis (NASH) rates are on the rise in industrialized nations, yet the mechanisms that contribute to disease development remain poorly defined. Here we sought to test the hypothesis that western diet (WD)‐induced NASH in obese juvenile Ossabaw swine is linked to cecal dysbiosis and altered markers of intestinal permeability, as well as to determine RNA transcriptomic changes within the liver in this model of pediatric NASH. Sixteen weeks of WD (high fat, fructose, cholesterol) feeding caused obesity and a severe NASH phenotype, including hepatocellular ballooning, inflammation, and fibrosis compared with lean pigs fed low fat chow. WD feeding induced marked cecal dysbiosis, including decreases in the relative abundance of Firmicutes (70% vs 50%, P<0.05) and a 6‐fold increase in Proteobacteria (23% vs 4%, p<0.001) vs chow fed pigs. Specifically, WD‐feeding increased relative abundances of classes Gammaproteobacteria and Deltaproteobacteria (gram‐negative genera Eschericia coli and Shigella) which are linked to endotoxemia, inflammation and intestinal permeability. The observed dysbiosis was associated with down regulation of jejunal mRNA expression of tight junction proteins ZO‐1 and ZO‐2, and increased mucosal cell expression of inflammatory markers CD‐14, TLR2, TLR4, and IL‐1β in obese WD‐fed pigs. RNA‐sequencing analyses revealed 2168 up‐ and 67 down‐regulated mRNA transcripts (≥ 2.0 fold, FDR <0.10) in liver between WD and chow fed swine. The top regulated canonical pathways identified by Ingenuity Pathway Analysis were “Interferon Signaling”, “Hepatic Fibrosis/Hepatic Stellate Cell Activation”, and “Antigen Presentation Pathway”. Collectively, these data demonstrate that WD feeding in juvenile Ossabaw swine induces cecal dysbiosis, alters markers of intestinal permeability, and causes robust transcriptomic changes in the liver that may contribute to NASH.Support or Funding InformationMizzou Advantage, Allen Foundation, and VA‐CDA2 IK2BX001299 (RSR)
Blockades of neuronal or endothelial synthases of nitric oxide have opposite effects on gastric bicarbonate secretion induced by mild irritation of the mucosa
Authors: Zolotarev Vasiliy A. , Andreeva Julia V. , Khropycheva Raisa P. 
Published: November 2023

In the gastric mucosa (GM), under normal physiological circumstances, an increase of endogenous nitric oxide (NO) level due to activity of constitutive synthases of NO is considered an important factor of gastric protection. However, the role of endogenous NO in regulation of gastric bicarbonate secretion, the main process of gastric protection, still is not fully understood. In particular, effects of endothelial (eNOS) and neuronal (nNOS) synthases of nitric oxide which are present almost in all types of GM cells were not compared.We examined roles of nNOS or eNOS in control of bicarbonate production induced by transient irritation of GM at normal conditions under anesthesia or after suppression of gastric acid secretion by omeprasol.In rats, concentration of HCO3− in stomach luminal perfusate was calculated basing on measurements of pH and PCO2. GM irritation for 20 min with acidic and hyperosmotic solution (1 M NaCl, pH 2.0) caused a marked and omeprazole‐independent increase of HCO3− secretion. The selective blocker of nNOS in vivo, 7‐nitroindazole (7‐NI), or the nonselective blocker of nNOS and eNOS, NG‐nitro‐L‐arginine (L‐NNA), was applied to the splanchnic circulation via retrograde injection into the splenic artery (1 mg/kg). At the normo‐acid state, irritation‐induced output of HCO3− was inhibited by 7‐NI but was not affected by L‐NNA. After administration of omeprazole, both 7‐NI and L‐NNA equally inhibited HCO3− production. Bicarbonate output was substantially reduced by the blocker of soluble guanylate cyclase (GC), methylene blue. Additionally, the effect of 7‐NI (but not L‐NNA) was abolished by a cyclooxygenase (COX) inhibitor, indomethacin. Infusion of NaHCO3 (10 mmol*kg−1*h−1, i.v.) did not change secretion of bicarbonates induced by irritation at the normo‐acid state but markedly enhanced HCO3− output after treatment with omeprazole. The last was inhibited by 7‐NI but was not affected by L‐NNA.We conclude that GM secretion of HCO3− caused by gastric intraluminal application of mild irritants is largely mediated by intramural nNOS and depends on GC‐COX interaction. Activity of nNOS promotes gastric transepithelial flux of HCO3− induced by irritation. Assuming that impacts of eNOS and nNOS on gastric bicarbonate secretion were additive, we determined a selective influence of eNOS indirectly by subtracting an effect of 7‐NI on HCO3− output from the effect of L‐NNA. It allows to speculate that eNOS activity causes COX‐independent reduction of HCO3− output in the normo‐acid stomach which was abolished by omeprazole. eNOS activity reduces transport of HCO3− from circulation to the surface of GM.
Gallbladder Motility And The Sex of The Guinea Pig
Authors: Kline Loren William , Karpinski Edward 
Published: November 2023

The sex hormones 17 β‐estradiol (E2), progesterone (P), and dihydrotestosterone (DHT) have all been shown to affect the motility of the gallbladder. A decrease in the motility of the gallbladder has been observed during pregnancy. This decrease in motility was attributed to elevated P levels. Gallstones are also more common in women than men. One suggested reason was that in gallbladders taken from women and men, women have more estrogen receptors than men, as well as, more P receptors than men. Both P and E2 had an inhibitory effect upon gallbladder contractility in men and premenopausal and postmenopausal women. Similar findings have been reported in gallbladder strips taken from male and female guinea pigs. In the present study, using pharmacologic techniques, there was no significant difference in the amount of E2‐, P‐, or DHT‐induced relaxation of CCK‐induced tension when the responses in gallbladder strips from male and female guinea pigs were compared at each concentration used. In addition, 3 metabolites of P were used‐17‐hydroxyprogesterone (17‐P), 20α ‐hydroxyprogesterone (20‐P), and 21‐hydroxyprogesterone (21‐P). There was no significant difference in the responses from strips from male and female guinea pigs at each concentration used. In order to determine if the effects of E2 and P were additive, strips from male animals were exposed to either E2 or P and the amount of relaxation recorded. After recovery the strips were exposed to E2 or P in reverse order to ensure the order of treatment had no effect. After recovery, the strips were treated with both E2 and P simultaneously and the relaxation recorded. This procedure was repeated with strips from female guinea pigs. The effect of E2 and P was found to be additive; suggesting that each hormone was acting through different messenger systems; however, the response of the strips from each sex were not significantly different. It is concluded that the sex of the guinea pig has no significant effect on the response to the sex hormones used.Support or Funding InformationInternal Grant