Jinglun Li

Synergistic effect of copper and arsenic upon oxidative stress, inflammation and autophagy alterations in brain tissues of Gallus gallus

Arsenic or copper is one of the most highly toxic pollution that can cause dysfunction to brains, however, the exact mechanism remains unclear. The aim of the study is to investigate the mechanisms of arsenic or/and copper-induced oxidative stress, inflammation and autophagy in chicken brains and elucidate the interactions between arsenic and copper. A total of 72 1-day-old Hy-line chickens were divided into four groups (18 chickens per group) treated with 30mg/kg arsenic trioxide (As2O3) or/and 300mg/kg copper sulfate (CuSO4) for 12weeks. Histological signs of inflammation were found in the cerebrum, cerebellum and brainstem exposure to arsenic or/and copper. The malondialdehyde (MDA) content were up-regulation, whereas oxidative damage parameters total antioxidant capacity (T-AOC), glutathione (GSH), the inhibition ability of hydroxyl radical (OH), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were significantly decreased (P<0.05). The mRNA levels and protein expressions of inflammation markers, such as nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2) and prostaglandin E synthase (PTGEs) were significantly increased (P<0.05). The mRNA levels and protein expressions of autophagy markers including phosphatidylinositol 3-kinase (PI3K), Akt, autophagy-related gene 5 (ATG5), microtubule-associated protein light chains 3 (LC3), ATG4B, and Becline1 in different regions of brains were up-regulation (P<0.05), except the mammalian target of rapamycin complex (mTORC). In conclusion, we speculated that arsenic or copper could induce oxidative stress, inflammation and autophagy in chicken brains, and there may have a synergistic effect between copper and arsenic.

Copper (II) and/or arsenite-induced oxidative stress cascades apoptosis and autophagy in the skeletal muscles of chicken

Arsenic (As) is a ubiquitous environmental toxin and robust inducer of oxidative stress (OxS). Copper (Cu) is an essential microelement, which participates in OxS as a cofactor for certain enzymes, with narrow optimal range between essential and toxic concentrations. However, their effects are rarely studied in chicken skeletal muscles, which have soaring per capita consumption andare susceptible to oxidative damage. In the present study, we demonstrated that the administration of copper sulfate (300 mg kg-1) or arsenite (30 mg kg-1) individually or their co-administration leads to varying degrees of OxS in the skeletal muscles of chickens. Corresponding to the protein expression pattern, the mRNA levels of caspase, B-cell lymphoma-2 (Bcl-2) families, and autophagy-related genes were also compromised in the experimental groups, indicating the involvement of both apoptotic and autophagic cell death. Additionally, rampant mitochondrial fission caused the vicious cycle between imbalanced mitochondrial dynamics and OxS, thus tethering intracellular homeostasis. The abovementioned muscle damage and index anomalies were time dependent, and more deteriorated effects were observed in Cu2+ and arsenite co-administered groups than those in groups administered Cu2+ and arsenite alone. Intriguingly, in the studied skeletal muscles, namely wing biceps brachii and leg gastrocnemius, there were conspicuous differences in oxidative toxicity susceptibility, which needs further study. The present study showed that Cu and/or As induce oxidative damage in chicken skeletal muscles and discussed its mechanism in terms of apoptosis, autophagy, and mitochondrial dynamics, thus voicing concerns about poultry breeding areas cross-contaminated with Cu2+ and arsenite.

Copper and arsenic-induced oxidative stress and immune imbalance are associated with activation of heat shock proteins in chicken intestines

ABSTRACT Arsenic and copper, two ubiquitous pollutants, can be oxidative stress inducers when organisms are heavy or chronically exposed, causing adverse effects on digestion and absorption function, resulting in potential losses to poultry husbandry. The present study examined the effects of arsenic trioxide (30mg/kg)‐ and copper sulfate (300mg/kg)‐mixed foods, administered alone or in combination for 12weeks, on various biochemical indices of oxidative stress and immunity in the small intestines of Hy‐line chickens. The results showed that for the first four weeks of exposure, both the redox and immune systems were unaffected. Subsequently, exposure to arsenic or copper significantly increased the level of lipid peroxidation (malondialdehyde and ability of anti‐hydroxy radical) concomitant with a collapse of the antioxidant system (catalase and glutathione peroxidase), in a time‐dependent manner. An increase in the mRNA and protein levels of pro‐inflammatory indicators (nuclear factor kappa B, cyclooxygenases‐2, tumor necrosis factor‐&agr; and prostaglandin E2 synthases) with a definite tendency toward Th1 (Th, helper T cell) cytokines was observed in both arsenic and copper treated chickens. Histologically, the destruction of the biofilm structure and inflammatory infiltrates was observed. Thus, in the intestine, heat shock proteins play protective roles against tissue damage. In some cases, we observed that the tissues of the small intestine were more sensitive to arsenic than to copper. Moreover, co‐exposure induced more serious intestinal toxicity than single treatment group, and this mechanism needs further exploration. HIGHLIGHTSCu and/or As induce intestinal toxicity by destructing antioxidant and immune system.Intestinal toxicity is more pronounced in co‐exposed groups than in individual.Duodenum seems more vulnerable to oxidative damage compared to jejunum and ileum.Heat shock proteins play intestinal protective function against tissues damage.

Copper or/and arsenic induce oxidative stress-cascaded, nuclear factor kappa B-dependent inflammation and immune imbalance, trigging heat shock response in the kidney of chicken

Excessive amount of copper (Cu) and inorganic arsenic (iAs) coexists in drinking water in many regions, this is associated with high risk of nephropathy, defined as chronic structural and functional disorders of the kidney. However, the underlying mechanisms are not well understood. In this study, a total of 72 day-old Hy-line chickens were exposed to 300 mg/kg copper sulphate or/and 30 mg/kg arsenic trioxide for 12 weeks. Indicators of oxidative stress, inflammation and heat shock proteins (HSPs) production were analyzed in kidney. The results showed that, when the toxicant was administrated alone, there is an antagonism between redox homeostasis during the first 4 weeks, which follows a collapse of antioxidant system manifested by damaged biomembrane structure. Whats worse, oxidative damage-cascaded histopathological lesions were accompanied by increases of proinflammatory mediators and an imbalance of “Th1/Th2 drift” (Th, helper T cell) regulated by nuclear factor kappa B (NF-κB). Simultaneously, intense heat shock response went with the organism. The above-mentioned renal lesions and indicators changes were time-dependent, more complex and deteriorated effects were observed in Cu/iAs combined groups compared with the others. This study supports Cu and iAs have a synergistic type on the nephro-toxicological process additively. In conclusion, oxidative stress and inflammatory induced by Cu or/and iAs are potential mechanisms in their nephrotoxicity, increased heat shock response may play a renoprotection function in tissues damage.

Assessment of 28 trace elements and 17 amino acid levels in muscular tissues of broiler chicken (Gallus gallus) suffering from arsenic trioxide

The contents of 28 trace elements, 17 amino acid were evaluated in muscular tissues (wings, crureus and pectoralis) of chickens in response to arsenic trioxide (As2O3). A total of 200 one-day-old male Hy-line chickens were fed either a commercial diet (C-group) or an As2O3 supplement diet containing 7.5mg/kg (L-group), 15mg/kg (M-group) or 30mg/kg (H-group) As2O3 for 90 days. The elements content was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Under As2O3 exposure, the concentration of As were elevated 8.87-15.76 fold, 7.93-15.63 fold and 5.94-12.45 fold in wings, crureus and pectoralis compared to the corresponding C-group, respectively. 19 element levels (lithium (Li), magnesium (Mg), aluminum (Al), silicon (Si), kalium (K), vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), selenium (Se), strontium (Sr), molybdenum (Mo), cadmium (Cd), tin (Sn), antimony (Sb), barium (Ba), mercury (Hg) and lead (Pb), 9 element levels (K, Co, Ni, Cu, As, Se, Sr, Sn, Ba and Hg) and 4 element levels (Mn, cobalt (Co), As, Sr and Ba) were significantly increased (P < 0.05) in wing, crureus and pectoralis, respectively. 2 element levels (sodium (Na) and zinc (Zn)), 5 element levels (Li, Na, Si, titanium (Ti and Cr), 13 element levels (Li, Na, Mg, K, V, Cr, iron (Fe), Cu, Zn, Mo, Sn, Hg and Pb) were significantly decreased (P < 0.05) in wing muscle, crureus and pectoralis, respectively. Additionally, in crureus and pectoralis, the content of total amino acids (TAA) was no significant alterations in L and M-group and then increased approximately 10.2% and 7.6% in H-group, respectively (P < 0.05). In wings, the level of total amino acids increased approximately 10% in L-group, whereas it showed unchanged in M and H-group compared to the corresponding C-group. We also observed that significantly increased levels of proline, cysteine, aspartic acid, methionine along with decrease in the tyrosine levels in muscular tissues compared to the corresponding C-group. In conclusion, the residual of As in the muscular tissues of chickens were dose-dependent and disrupts trace element homeostasis, amino acids level in muscular tissues of chickens under As2O3 exposure. Additionally, the response (trace elements and amino acids) were different in wing, thigh and pectoral of chick under As2O3 exposure. This study provided references for further study of heavy metal poisoning and may be helpful to understanding the toxicological mechanism of As2O3 exposure in muscular tissues of chickens.

Copper or/and arsenic induces autophagy by oxidative stress-related PI3K/AKT/mTOR pathways and cascaded mitochondrial fission in chicken skeletal muscle

Autophagy is an ubiquitin proteasome system for degradation of intracellular damaged proteins and organelles. Both as environmental pollutants, flourishing data show arsenic (As) and copper (Cu) as robust oxidative stress inducers. Whether this kind of damage correlates with autophagy through the phosphoinositide-3-kinase/protein kinase b/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway still remains elusive. A 12-week exposures of Cu or/and As to chicken time-dependently displayed significant element residue in the pectoralis. Aligning with previous results, a strong pro-oxidant nature of Cu and As was clearly indicated by enzyme/nonenzyme antioxidants. Fragmented mitochondria induced by oxidative damage were accompanied by overexpressed dynamin related protein-1 and decreased mitochondrial fusion-related genes. Upon comparative analysis, time-dependent conversion of light chain 3 (LC3)-I to LC3-II, increases in autophagy-related genes such as Bcl-2-interacting protein (Beclin-1) and inhibited PI3K/AKT/mTOR pathway firmly supported the fact that Cu or/and As induces autophagy. These results further coincided with ultrastructure showing clusters of vesicles and autophagosome in the skeletal muscle. Interestingly, the time-dependently elevated heat shock proteins observed in Cu or/and As treated chicken suggest the continuous adaptation and physiological acclimation of organisms to this stress responses. Interestingly, the combination of copper and arsenic elicited more serious oxidative damage and its-cascaded injuries than their individuals. Together, our results showed that after Cu or/and As insult and accumulation, inhibited PI3K/AKT/mTOR pathway activated autophagy and disturbed mitochondrial dynamic, forming a positive feedback with redox disorder.

Molecular cloning and functional characterization of eleven subtypes of interferon-α in Amur tigers (Panthera tigris altaica)

Interferon has a broad-spectrum of antiviral effects and represents an ideal choice for the development of antiviral drugs. Nonetheless, information about alpha interferon (IFN-α) is vacant in Amur tiger (Panthera tigris altaica), an endangered species and indigenous to northeast Asia. Herein, 11 PtIFN-αs genes, which encoded proteins of 164-165 amino acids, were amplified. Afterwards, expression and purification were conducted in Escherichia coli. In physicochemical analysis, PtIFN-αs were shown to be highly sensitive to trypsin and remained stable despite changes in pH and temperature. In feline kidney cells (F81)/vesicular stomatitis virus (VSV)/canine distemper virus (CDV)/avian influenza virus (AIV) systems, PtIFN-αs were demonstrated to have distinct antiviral activities, some of them (PtIFN-α and PtIFN-α9) inhibited viral transcription levels more effectively than the other subtypes including Felis catus IFN-α, an effective therapeutic agent used for viral infections clinically. Additionally, PtIFN-α and PtIFN-α9 can up-regulate the transcription and expression of p53, a tumor suppressor factor, which could promote apoptosis of virus-infected cells. In conclusion, we cloned and expressed 11 subtypes of PtIFN-α for the first time. Furthermore, PtIFN-α and PtIFN-α9 were likely to be more efficient against both chronic viral infections and neoplastic diseases that affect the Amur tiger population. It will be of significant importance for further studies to protect this endangered species.

The apoptosis in arsenic-induced oxidative stress is associated with autophagy in the testis tissues of chicken

ABSTRACT The aim of this study is to investigate whether arsenic (As) could induce testicular poisoning and influence the oxidative stress, apoptosis and autophagy in chickens. Seventy‐two 1‐day‐old male Hy‐line chickens were divided into 4 groups which were exposed to 0, 0.625, 1.25, and 2.5 mg/kg body weight (BW) of arsenic trioxide (As2O3) for 30, 60 and 90 days, respectively. Histological and ultrastructural changes, antioxidant enzyme activity, mRNA and protein levels of apoptosis and autophagy‐related genes were detected. Oxidative stress injuries were obvious in the testes exposure to As2O3, which resulted in the decreased activities of antioxidant enzymes, such as catalase (CAT) and superoxide dismutases (SOD). Meanwhile, the changes of mRNA and protein levels of apoptosis and autophagy‐related genes showed that As2O3 exposure induced enhanced testicular apoptosis and increased the levels of autophagy markers such as Microtubule associated protein light chains 3‐II (LC3‐II), dynein, Beclin‐1, Autophagy associated gene 5 (ATG5) and ATG4B but not LC3‐I and mammalian target of rapamycin (mTOR), and demonstrated the cross‐talk between apoptosis and autophagy. Histological and ultrastructural abnormalities confirm the changes of the above indicators. Taken together, our findings provide deeper insights into roles of excessive apoptosis and autophagy in the aggravation of testicular damage, which could contribute to a better understanding of As2O3‐induced testicular poisoning in chickens.