Search Results (47)

Background/Objectives: Hypertension is a major contributor to cardiovascular diseases and is often intensified by psychological stress, which can also affect bone metabolism. Although both conditions independently compromise bone health, their combined impact—particularly under acute and chronic stress—remains unclear. This pilot study aimed to assess the effects of such stressors on bone structure in spontaneously hypertensive rats (SHRs). Methods: Forty male rats, both normotensive and SHRs, were randomly assigned to control, acute stress, or chronic stress groups. Acute stress involves a single 2 h physical restraint. Chronic stress was induced over 10 days using alternating stressors: agitation, forced swimming, physical restraint, cold exposure, and water deprivation. Tibial bones were analyzed by microcomputed tomography (micro-CT), and histology was performed using Hematoxylin and Eosin and Masson’s Trichrome stains. Results: Micro-CT showed increased trabecular bone volume in normotensive rats under chronic stress, whereas SHRs displayed impaired remodeling under both stress types. Histological analysis revealed preserved connective tissue overall but evident changes in growth plate structure among stressed rats. SHRs exhibited exacerbated trabecular formation and cartilage abnormalities, including necrotic zones. Conclusions: Both acute and chronic stress, especially in the context of hypertension, negatively affect bone remodeling and maturation. Despite the absence of overt inflammation, structural bone changes were evident, indicating potential long-term risks. These findings highlight the importance of further studies on stress–hypertension interactions in bone health as well as the exploration of therapeutic approaches to mitigate skeletal damage under such conditions. Full article

Controlling low ambient temperatures and ammonia levels is critical for effective environmental management in poultry houses during winter, as both represent persistent stressors affecting bird health and productivity. However, evidence regarding their combined long-term effects on the physiological responses of laying hens remains limited. In this study, 576 eighteen-week-old Hy-Line Brown hens were randomly assigned to six treatments (8 replicates with 12 birds per replicate each treatment) and housed in environmentally controlled chambers for 20 weeks: T1 (8 °C, ≤5 ppm ammonia), T2 (8 °C, 20 ppm ammonia), T3 (8 °C, 45 ppm ammonia), T4 (20 °C, ≤5 ppm ammonia; control), T5 (20 °C, 20 ppm ammonia), and T6 (20 °C, 45 ppm ammonia). Plasma samples were collected at 22, 26, 30, 34, and 38 weeks to evaluate physiological stress biomarkers (corticosterone, CORT; total antioxidant capacity, T-AOC), immunoglobulins (IgG, IgM, and IgA), and reproductive hormones (luteinizing hormone, LH; follicle-stimulating hormone, FSH; estradiol, E2). At 38 weeks, hypothalamus, pituitary, and spleen tissues were collected to assess the relative mRNA expression of gonadotropin-releasing hormone (GnRH), FSH, tumor necrosis factor-α (TNF-α), and interleukins (IL-1β, IL-6, and IL-10). Results showed that both cold and ammonia stress reduced antioxidant capacity, disrupted immune homeostasis, and altered reproductive hormone profiles. Cold exposure induced acute immunoendocrine alterations with partial physiological adaptation over time, whereas ammonia exerted progressive and cumulative damage, including elevated immunoglobulins (IgG and IgM) and downregulation of GnRH and FSH expression. Combined exposure significantly upregulated TNF-α and IL-1β expression, suggesting a synergistic inflammatory response. These results highlight complex, parameter-specific interactions between cold and ammonia stressors, emphasizing the need for targeted environmental strategies. Stage-specific interventions—thermal regulation in early laying and ammonia control in later phases—are recommended to safeguard hen health and optimize productivity under winter conditions. Full article

Chronic cold exposure is a stressor that may adversely affect the hippocampal structure and cognitive function. Critical for memory formation and learning processes, the hippocampus is particularly susceptible to hypothalamic–pituitary–adrenal (HPA) axis activity and elevated glucocorticoid levels. Vitamin D plays a complex role in regulating mitochondrial function and may provide neuroprotection. This study aimed to investigate the effects of chronic cold exposure on proteins associated with signaling pathways, mitochondrial function, and oxidative stress in the hippocampus of rats and to evaluate the neuroprotective potential of vitamin D3 supplementation. Male Wistar rats (n = 26) were assigned to four groups: control (CON; n = 4), sham stress (WW; n = 6), chronic cold water immersion (CCWI) (CW group; n = 8), and CCWI with 600 IU/kg/day vitamin D3 (VD3) supplementation (CW + D group; n = 8). Exposure to CCWI significantly reduced the hippocampal mass of rats, an effect not reversed by vitamin D3 supplementation. However, vitamin D3 improved mitochondrial function and exhibited antioxidant effects, partially reducing markers of protein and lipid free radicals damage in neural tissue. Our findings demonstrate the antioxidant properties of VD3 and its potential role in mitigating hippocampal damage during prolonged cold exposure, although its neuroprotective effects remain limited. Full article

Background: Snapper is a significant commercial, recreational, and cultural teleost species in New Zealand, with aquaculture potential. The impact of long-term (chronic) temperature changes on immune and stress responses have not been studied in snapper, yet they have a critical importance to the health status of the fish. Methods: We investigated a set of genes in 30 individual snapper including fin, head kidney, and liver tissue, fish (10 per group) were exposed to either warm (22 °C), cold (14 °C), or ambient temperatures (10.5–18.6 °C) for 3 months. Results: Analyses of experimental fish using NanoString technologies to assess stress- and immune-related genes in the three tissue types showed that 22 out of 25 genes changed significantly in the experiment, indicating the significant impacts of chronic temperature changes on stress and immune responses. Furthermore, using a combined dataset based on this study and a previous one testing the impact of acute temperature changes in snapper, we identified five genes in the non-lethal fin-clip samples that can predict internal organ health status. Conclusions: Taken together, our experiments demonstrate the potential of the NanoString gene expression assessment tool for the rapid monitoring of stress responses in snapper, which can aid in the selection of stress-resilient wild stocks, monitor species in aquaculture environments, and inform the selection of locations for aquaculture. Full article

Menthol, the primary active compound in the widely cultivated peppermint plant (Mentha piperita), is well known for its use in human products such as topical analgesics and cold remedies. Menthol’s cooling sensation and ability to locally modulate pain through interactions with transient receptor potential channels make it a valuable bioactive compound. In recent years, menthol’s antimicrobial, anti-inflammatory, and antioxidative properties have drawn attention in the livestock industry as a natural alternative to synthetic antibiotics in feed additives. This review comprehensively examines the existing literature to assess menthol’s effects on animal growth performance, product quality, immune function, gastrointestinal microbial ecosystems, and metabolism across various livestock species. Notably, menthol shows potential for improving feed efficiency, mitigating chronic inflammation and oxidative stress, inhibiting environmental and gastrointestinal pathogens, and enhancing calcium absorption. However, optimal dosages, treatment durations, synergies with other phytogenic compounds, and regulatory mechanisms require further investigation. Additionally, with increasing global temperatures and growing concerns about animal welfare, menthol’s cooling, methane-reducing, and analgesic properties present promising opportunities for advancing sustainable livestock practices. Full article

Background: Fibromyalgia, a chronic condition that causes long-lasting pain over several months, is a global medical issue with both personal and societal implications. It is one of the hardest types of pain to heal, given the lack of objective parameters for diagnosis and progression evaluation. The main symptoms of fibromyalgia are long-lasting widespread pain alongside with anxiety, fatigue, sleep disorders, cognitive dysfunction, and obesity. Programmed cell death 1 ligand 1 (PD-L1) has been used as a target in cancer immunotherapy. It can inhibit acute and chronic pain by suppressing nociceptive neuron activity via PD-1 receptors. Methods: The current study aimed to investigate the role of PD-L1/PD1 in a mouse fibromyalgia pain model. Mice were exposed to intermittent cold stress (ICS) to produce a murine fibromyalgia model characterized using von Frey and Hargreaves tests. Results: The ICS-induced mice fibromyalgia pain model showed mechanical (2.26 ± 0.18 g) and thermal (4.36 ± 0.31 s) hyperalgesia. Nociceptive responses could be relieved with electroacupuncture, intracerebral PD-L1 injection, or Trpv1 deletion. We also identified a lower PD-1 level in the dorsal root ganglion, spinal cord, thalamus, and somatosensory cortex. In contrast, levels of pain-related kinases increased after fibromyalgia induction, an effect which could be reversed by EA, PD-L1, or Trpv1 deletion. Conclusions: Our findings shed light on the contribution of PD-L1/PD1 to EA and fibromyalgia pain, indicating its potential as a treatment target for fibromyalgia. Full article

Diabetic foot ulcers have an enormous impact on patients’ quality of life and represent a major economic burden. The cause is delayed and incomplete wound healing due to hyperglycemia, reduced blood flow, infections, oxidative stress and chronic inflammation. Plasma-activated water (PAW) is emerging as a new therapeutic approach in wound treatment, as it has many of the advantages of cold atmospheric plasma but is easier to apply, thus allowing for widespread use. The aim of this study was to investigate the potential of PAW to improve wound healing in diabetic rats, with a focus on uncovering the underlying mechanisms. Two full-thickness wounds in control and diabetic animals were treated with PAW, and healing was monitored for 15 days at five time points. PAW improved wound healing in diabetic rats and mainly affected the inflammatory phase of wound healing. Application of PAW decreased the number of inflammatory cells, myeloperoxidase (MPO) and N-acetyl-b-D-glycosaminidase (NAG) activity, as well as the mRNA expression of proinflammatory genes in diabetic rats. Ten days after injury, PAW treatment increased collagen deposition in the diabetic animals by almost 10% without affecting collagen mRNA expression, and this is in correlation with a decrease in the Mmp-9/Timp-1 ratio. In conclusion, PAW treatment affects wound healing by reducing the inflammatory response and influencing extracellular matrix turnover, suggesting that it has great potential to accelerate the healing of diabetic wounds. Full article

Background: Fibromyalgia (FM) is characterized by chronic pain, significantly affecting the quality of life and functional capabilities of patients. In addition to pain, patients may experience insomnia, chronic fatigue, depression, anxiety, and headaches, further complicating their overall well-being. The Transient Receptor Potential Vanilloid 1 (TRPV1) receptor responds to various noxious stimuli and plays a key role in regulating pain sensitivity and inflammation. Thus, targeting TRPV1 may provide analgesic and anti-inflammatory benefits. This study investigates the efficacy of electroacupuncture (EA) in alleviating chronic pain in FM through TRPV1 and its downstream molecules in the central nervous system (CNS). Methods: To model FM, we subjected mice to intermittent cold stress (ICS) for three days. The study comprised five rodent groups: Control (CON), ICS, ICS + EA, ICS + Sham EA, and ICS + KO (TRPV1 knockout mice). Results: Our findings revealed that ICS induced allodynia and hyperalgesia in mice by day four, persisting until day 21. EA at 2 Hz and TRPV1 KO significantly decreased both mechanical and thermal hypersensitivity (Withdrawal—Day 14: 2.43 ± 0.19 g; Day 21: 5.88 ± 0.47 g, n = 6, p < 0.05; Latency—Day 14: 2.77 ± 0.22 s; Day 21: 5.85 ± 0.41 s, n = 6, p < 0.05). In contrast, sham EA did not produce significant effects. Additionally, TRPV1 and several pain-related proteins were significantly elevated in the thalamus, somatosensory cortex (SSC), medial prefrontal cortex (mPFC), hippocampus, hypothalamus, cerebellum regions V (CB V), VI (CB VI) and VII (CB VII) after the ICS model. Both EA at the ST36 acupoint and TRPV1 KO mice showed diminished overexpression of pain-related proteins, with the sham EA group showing no significant changes compared to the ICS group. Conclusions: Chronic widespread pain was reduced by EA and TRPV1 KO, with the effects of EA on the TRPV1 pain pathway clearly evident in the CNS after 21 days. Full article

Fibromyalgia is a chronic illness usually accompanied by long-lasting, general pain throughout the body, often accompanied by anxiety, depression, fatigue, and sleep disruption. Meanwhile, doctors and scientists have not entirely discovered detailed mechanisms; patients always have an exaggerated sensation to pervasive pain without satisfied medical service. Given the lack of knowledge on its underlying mechanism, current treatments aim to provide pain and/or symptom relief. The present study aimed to clarify the role of cannabinoid receptor 1 (CB1) signaling in a mouse fibromyalgia pain model. To develop the mouse fibromyalgia model, mice were subjected to intermittent cold stress (ICS). Our results indicated that mechanical (2.09 ± 0.09 g) and thermal hyperalgesia (4.77 ± 0.29 s), which were evaluated by von Frey and Hargraves’ tests, were induced by ICS, suggesting successful modeling. The hurting replies were then provoked by electroacupuncture (EA) but not for sham EA mice. Further, in a Western blot analysis, we found significantly decreased CB1 protein levels in the thalamus, somatosensory cortex, and anterior cingulate cortex. In addition, the levels of pain-related protein kinases and transcription factor were increased. Treatment with EA reliably increased CB1 expression in various brain regions sequentially alleviated by nociceptive mediators. Furthermore, the administration of a CB1 agonist significantly attenuated fibromyalgia pain, reversed EA analgesia by the CB1 antagonist, and further reversed the chemogenetic inhibition of SSC. Our innovative findings evidence the role of CB1 signaling in the interaction of EA and fibromyalgia, suggesting its potential for clinical trials and as a treatment target. Full article

Oxidative stress and chronic inflammation create a perpetual cycle in the elderly, where impaired immune function amplifies susceptibility to oxidative damage, and oxidative stress further weakens the immune response. This cycle is particularly detrimental to the respiratory system of the elderly, which is an easy target for constant exogenous harmful attacks during cold/flu season or under heavy air pollution. Herbal medicines that protect respiratory function are seen as safer alternatives to conventional therapies; however, there is limited availability of scientifically validated, safe, and effective natural supplements for these conditions. In this study, we evaluated a standardized bioflavonoid composition, UP446, that contains bioactives from the roots of Scutellaria baicalensis and the heartwoods of Acacia catechu as a natural and nutritional supplement for its antioxidative and immunoregulatory effects in oxidative stress-accelerated aging and chemically induced immune suppression mouse models. Immunosenescence was induced through the repeated subcutaneous inoculation of D-galactose (D-Gal) at a dose of 500 mg/kg/day in CD-1 mice. UP446 was administered orally at doses of 100 mg/kg and 200 mg/kg starting in the fifth week of immunosenescence induction. This study lasted a total of ten weeks. All mice received a quadrivalent influenza vaccine 2 weeks before termination. Whole blood, serum, spleen homogenate, and thymus tissues were processed for analysis. Cyclophosphamide (Cy)-induced immunosuppression was triggered by three consecutive injections of cyclophosphamide at 80 mg/kg/day, followed by the oral administration of UP446 for 18 days at doses of 100 mg/kg and 200 mg/kg. Blood was collected from each animal at necropsy, and serum was isolated for IgA and IgG ELISA analysis. UP446 was found to improve immune response, as evidenced by the stimulation of innate (NK cells) and adaptive immune responses (T cells and cytotoxic T cells), an increase in antioxidant capacity (glutathione peroxidase), the preservation of vital immune organs (the thymus), and a reduction in NFκB. UP446 also increased serum levels of IgA and IgG. The findings presented in this report demonstrate the antioxidative, anti-inflammatory, and immune-regulatory activities of UP446, suggesting its potential use in respiratory conditions involving immune stress due to aging, oxidative stress, and/or pathogenic challenges. Full article

Chronic stress has become a major problem that endangers people’s physical and mental health. Studies have shown that chronic stress impairs female reproduction. However, the related mechanism is not fully understood. P2X7 receptor (P2X7R) is involved in a variety of pathological changes induced by chronic stress. Whether P2X7R is involved in the effect of chronic stress on female reproduction has not been studied. In this study, we established a chronic restraint stress mouse model and chronic cold stress mouse model. We found that the number of corpora lutea was significantly reduced in the two chronic stress models. The number of corpora lutea indirectly reflects the ovulation, suggesting that chronic stress influences ovulation. P2X7R expression was significantly increased in ovaries of the two chronic stress models. A superovulation experiment showed that P2X7R inhibitor A-438079 HCL partially rescued the ovulation rate of the two chronic stress models. Further studies showed that activation of P2X7R signaling inhibited the cumulus expansion and promoted the expression of NPPC in granulosa cells, one key negative factor of cumulus expansion. Moreover, sirius red staining showed that the ovarian fibrosis was increased in the two chronic stress models. For the fibrosis-related factors, TGF-β1 was increased and MMP2 was decreased. In vitro studies also showed that activation of P2X7R signaling upregulated the expression of TGF-β1 and downregulated the expression of MMP2 in granulosa cells. In conclusion, P2X7R expression was increased in the ovaries of the chronic restraint-stress and chronic cold-stress mouse models. Activation of P2X7R signaling promoted NPPC expression and cumulus expansion disorder, which contributed to the abnormal ovulation of the chronic stress model. Activation of P2X7R signaling is also associated with the ovarian fibrosis changes in the chronic stress model. Full article

Recent studies revealed that the high production of reactive oxidative species due to exposure to fine or ultrafine particles are involved in many chronic respiratory disorders. However, the poor standard of clinical data in sub-Saharan countries makes the assessment of our knowledge on the health impacts of air pollution in urban cities very difficult. Objective: The aim of this study was to evaluate the distribution of respiratory disorders associated with exposure to fine and ultrafine air particles through the changes of some oxidative stress biomarkers among motorbike drivers from two cities of Cameroon. Methods: A cross-sectional survey using a standardized questionnaire was conducted in 2019 on 191 motorcycle drivers (MDs) working in Douala and Dschang. Then, the activities of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) were measured using colorimetric methods. The data of participants, after being clustered in Microsoft Excel, were analyzed and statistically compared using SPSS 20 software. Results: The motorbike drivers recruited from both cities were from 21 to 40 years old, with a mean age of 29.93 (±0.82). The distribution of respiratory disorders, such as a runny nose, cold, dry cough, chest discomfort, and breathlessness, was significantly increased among MDs in Douala. According to the results of biological assays, SOD and MDA were significantly greater among the MDs recruited in Douala compared to those of Dschang. The change in these oxidative stress markers was significantly positively correlated with the mobilization of monocytes and negatively correlated with neutrophils, showing the onset and progression of subjacent inflammatory reactions, and it seemed to be significantly influenced by the location MDs lived in. Conclusions: Through this study, we have confirmed the evidence supporting that the onset and progression of oxidative stress is caused by the long-term exposure to fine or ultrafine air particles among working people living in urban cities. Further studies should be conducted to provide evidence for the cellular damage and dysfunction related to the chronic exposure to fine particulate matter (PM) in the air among working people in the metropolitan sub-Saharan Africa context. Full article

This paper aims to provide an updated review and current understanding of the impact of extreme temperatures—focusing on heat stress (HS)—on the quality of pork and poultry meat, particularly amidst an unprecedented global rise in environmental temperatures. Acute or chronic HS can lead to the development of pale, soft, and exudative (PSE) meat during short transportation or of dark, firm, and dry (DFD) meat associated with long transportation and seasonal changes in pork and poultry meat. While HS is more likely to result in PSE meat, cold stress (CS) is more commonly linked to the development of DFD meat. Methods aimed at mitigating the effects of HS include showering (water sprinkling/misting) during transport, as well as control and adequate ventilation rates in the truck, which not only improve animal welfare but also reduce mortality and the incidence of PSE meat. To mitigate CS, bedding on trailers and closing the tracks’ curtains (insulation) are viable strategies. Ongoing efforts to minimize meat quality deterioration due to HS or CS must prioritize the welfare of the livestock and focus on the scaleup of laboratory testing to commercial applications. Full article

During diapause, a state of temporarily arrested development, insects require low winter temperatures to suppress their metabolism, conserve energy stores and acquire cold hardiness. A warmer winter could, thus, reduce diapause incidence and duration in many species, prematurely deplete their energy reserves and compromise post-diapause fitness. In this study, we investigated the combined effects of thermal stress and the diapause program on the expression of selected genes involved in antioxidant defense and heat shock response in the European corn borer Ostrinia nubilalis. By using qRT-PCR, it has been shown that response to chronic heat stress is characterized by raised mRNA levels of grx and trx, two important genes of the antioxidant defense system, as well as of hsp70 and, somewhat, of hsp90, two major heat shock response proteins. On the other hand, the expression of hsc70, hsp20.4 and hsp20.1 was discontinuous in the latter part of diapause, or was strongly controlled by the diapause program and refractory to heat stress, as was the case for mtn and fer, genes encoding two metal storage proteins crucial for metal ion homeostasis. This is the first time that the effects of high winter temperatures have been assessed on cold-hardy diapausing larvae and pupae of this important corn pest. Full article

Fibromyalgia (FM) is a complex, chronic, widespread pain syndrome that can cause significant health and economic burden. Emerging evidence has shown that neuroinflammation is an underlying pathological mechanism in FM. Toll-like receptors (TLRs) are key mediators of the immune system. TLR4 is expressed primarily in microglia and regulates downstream signaling pathways, such as MyD88/NF-κB and TRIF/IRF3. It remains unknown whether electroacupuncture (EA) has therapeutic benefit in attenuating FM pain and what role the TLR4 pathway may play in this effect. We compared EA with sham EA to eliminate the placebo effect due to acupuncture. We demonstrated that intermittent cold stress significantly induced an increase in mechanical and thermal FM pain in mice (mechanical: 2.48 ± 0.53 g; thermal: 5.64 ± 0.32 s). EA but not sham EA has an analgesic effect on FM mice. TLR4 and inflammatory mediator-related molecules were increased in the thalamus, medial prefrontal cortex, somatosensory cortex (SSC), and amygdala of FM mice, indicating neuroinflammation and microglial activation. These molecules were reduced by EA but not sham EA. Furthermore, a new chemogenetics method was used to precisely inhibit SSC activity that displayed an anti-nociceptive effect through the TLR4 pathway. Our results imply that the analgesic effect of EA is associated with TLR4 downregulation. We provide novel evidence that EA modulates the TLR4 signaling pathway, revealing potential therapeutic targets for FM pain. Full article