Alterations in mitochondrial function and spermatozoal motility in goat spermatozoa following incubation with a human lysozyme plasmid

Comparison of two methods of sperm- and testis-mediated gene transfer in production of transgenic animals: A systematic review

Transgenic (Tg) animal technology is one of the growing areas in biology. Various Tg technologies, each with its own advantages and disadvantages, are available for generating Tg animals. These include zygote microinjection, electroporation, viral infection, embryonic stem cell or spermatogonial stem cell-mediated production of Tg animals, sperm-mediated gene transfer (SMGT), and testis-mediated gene transfer (TMGT). However, there are currently no comprehensive studies comparing SMGT and TMGT methods, selecting appropriate gene delivery carriers (such as nanoparticles and liposomes), and determining the optimal route for gene delivery (SMGT and TMGT) for producing Tg animal. Here we aim to provide a comprehensive assessment comparing SMGT and TMGT methods, and to introduce the best carriers and gene transfer methods to sperm and testis to generate Tg animals in different species. From 2010 to 2022, 47 studies on SMGT and 25 studies on TMGT have been conducted. Mice and rats were the most commonly used species in SMGT and TMGT. Regarding the SMGT approach, nanoparticles, streptolysin-O, and virus packaging were found to be the best gene transfer methods for generating Tg mice. In the TMGT method, the best gene transfer methods for generating Tg mice and rats were virus packaging, dimethyl sulfoxide, electroporation, and liposome. Our study has shown that the efficiency of producing Tg animals varies depending on the species, gene carrier, and method of gene transfer.

The translocase of the inner mitochondrial membrane 22-2 is required for mitochondrial membrane function during Arabidopsis seed development

The carrier translocase (also known as translocase of the inner membrane 22; TIM22 complex) is an important component of the mitochondrial protein import apparatus. However, the biological functions of AtTIM22-2 in Arabidopsis remain poorly defined. Here, we report studies on two tim22-2 mutants that exhibit defects in embryo and endosperm development, leading to seed abortion. AtTIM22-2, which was localized in mitochondria, was widely expressed in embryos and in various seedling organs. Loss of AtTIM22-2 function resulted in irregular mitochondrial cristae, decreased respiratory activity, and a lower membrane potential, together with changes in gene expression and enzyme activity related to reactive oxygen species (ROS) metabolism, leading to increased accumulation of ROS in the embryo. The levels of transcripts encoding mitochondrial protein import components were also altered in the tim22-2 mutants. Furthermore, mass spectrometry, bimolecular fluorescence complementation and co-immunoprecipitation assays revealed that AtTIM22-2 interacted with AtTIM23-2, AtB14.7 (a member of Arabidopsis OEP16 family encoded by At2G42210), and AT5G27395 (mitochondrial inner membrane translocase complex, subunit TIM44-related protein). Taken together, these results demonstrate that AtTIM22-2 is essential for maintaining mitochondrial membrane functions during seed development. These findings lay the foundations for a new model of the composition and functions of the TIM22 complex in higher plants.

Methylprednisolone improves the quality of liquid preserved boar spermatozoa in vitro and reduces polymorphonuclear neutrophil chemotaxis and phagocytosis

After artificial insemination, immune cells such as polymorphonuclear neutrophils will be recruited into the genital tract and induce endometrial inflammation, adversely affecting the spermatozoa. This study aimed to analyze the effect of methylprednisolone (MPS) on boar spermatozoa quality of in vitro liquid preservation and chemotaxis and phagocytosis of polymorphonuclear neutrophils toward boar spermatozoa. Various concentrations of MPS were added to the extender and analyzed for their effects on spermatozoa motility, kinetic parameters, abnormality rate, total antioxidant capacity (T-AOC) levels, H₂O₂ content, mitochondrial membrane potential and acrosome integrity. Testing of MPS on chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa induced by lipopolysaccharide (LPS). The results showed that an extender containing 2 × 10^-7 mol/mL MPS was the most effective for preserving boar spermatozoa during in vitro liquid preservation at 17°C. It effectively improved spermatozoa motility, kinetic parameters, T-AOC levels, mitochondrial membrane potential and acrosome integrity, reducing the abnormality rate and H₂O₂ content. Meanwhile, the chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa under LPS induction were inhibited in a concentration-dependent manner. In conclusion, MPS has positive implications for improving in vitro liquid preserved boar spermatozoa quality, inhibiting chemotaxis and phagocytosis of polymorphonuclear neutrophils toward spermatozoa.

Fluorescence Imaging-Incorporated Transcriptome Study of Glutathione Depletion-Enhanced Ferroptosis Therapy via Targeting Gold Nanoclusters

Ferroptosis plays an important role in tumor inhibition and is a new type of programmed cell death. Recent studies have shown that glutathione (GSH) depletion is an effective method to enhance the therapeutic efficacy of ferroptosis; however, a systematic investigation of the phenomenon is limited. Herein, we provide a facile fluorescence imaging-incorporated transcriptome strategy to visualize the process and explore the mechanism of GSH depletion-enhanced ferroptosis. The proposed multifunctional nanoplatform is achieved using simple transferrin receptor aptamer-functionalized fluorescent gold nanoclusters (termed TfRA-AuNCs), which exhibit efficient hydroxyl radical generation and GSH-depleting capabilities. Live cell fluorescence imaging results revealed that TfRA-AuNCs were endocytosed into 4T1 cells and were mostly distributed in lysosomes. In vitro results indicated that TfRA-AuNCs enhanced the ferroptosis effect in 4T1 cells. Importantly, transcriptome analysis indicated that 4T1 cells treated with TfRA-AuNCs regulated the expression change of ferroptosis-related genes, and the Kyoto Encyclopedia of Genes and Genomes pathway identified the GSH metabolism pathway involved in ferroptosis, thus revealing the exact molecular mechanism of ferroptosis induced by TfRA-AuNCs at the RNA level. Furthermore, in vivo results confirmed the tumor inhibition effect, tumor-targeted fluorescence imaging, and long-term biocompatibility after TfRA-AuNC treatment. This study introduces a new possibility for the mechanistic study of nanoagent-induced ferroptosis in tumor treatment.

Exogenous spermidine effectively improves the quality of cryopreserved boar sperm

Boar sperm are less resistant to the dramatic environmental changes that occur during in vitro preservation. Spermidine has various physiological functions including the anti-oxidative effect. The main objective of this study was to clarify whether spermidine could protect boar sperm from the attack of reactive oxygen species under cryopreservation treatment. We set the concentrations of spermidine at 0, 2, 4, 6, and 8 mmol/L and evaluated the effects of spermidine on sperm motility, viability, malformation rates, kinetic parameters, membrane integrity, mitochondrial activity, DNA integrity, H2 O2 content, malondialdehyde content, total antioxidant capacity, and antioxidant enzyme activity. Finally, the effects of spermidine on the sperm fertility were assessed by artificial insemination. The results showed that spermidine improved various physiological parameters of sperm in a dose-dependent manner. The quality and antioxidant capacity of sperm cryopreserved with 6 mmol/L spermidine were significantly less reduced (P < 0.05), and the contents of malformation rate, H2 O2 , and malondialdehyde content were significantly decreased (P < 0.05). The significant increase in the number of litters indicated the possibility that spermidine had important practical value in pig reproduction (P < 0.05). Therefore, the addition of appropriate concentrations of spermidine to cryopreservation extenders may effectively improve the quality of boar sperm for in vitro preservation.

Mitochondrial dysfunction and mitophagy pathway activation in hepatitis E virus-infected livers of Mongolian gerbils

Recently, hepatitis E virus (HEV) has caused large outbreaks and presented a significant public health problem. Thus, the mechanism of HEV has attracted increasing research attention. Previous studies revealed that HEV infection induced hepatocyte injuries and structural and functional changes in mitochondria. These pathological changes affected the life cycle of hepatocytes. However, the precise underlying mechanism and the effector protein responsible for this process remain unclear. In the present study, mitochondrial function and the expression of mitophagy-associated mRNA transcripts and proteins were detected in an HEV- infected Mongolian gerbil model. Observation of ultrastructural changes in the liver of the inoculated group revealed the disappearance of mitochondrial cristae of mitochondrion, blurring of the bilayer structure and cavitation in the cytoplasm. The results showed that the mitochondrial transmembrane potential of decreased, mitochondrial transition pore (MPTP) opening increased, reactive oxygen species (ROS) production increased, and glutathione peroxidase (GSH-Px) activity decreased in the HEV-inoculated group. Moreover, the LC3, Beclin1, BNIP3L, Parkin, PINK1 and P62 mRNA levels were significantly increased (p < 0.05 and p < 0.01) in the inoculated group. Western blot and immunohistochemistry assay analyses detected the upregulation of the mitophagy-associated proteins LC3, Beclin1, BNIP3L, Parkin, PINK1 and P62 (p < 0.05 and p < 0.01) in HEV-infected gerbils. All these data demonstrated that HEV infection in vivo induced mitochondrial dysfunction and the activation of the mitophagy pathway, which might be one of the key factors in hepatocyte injury.

Resveratrol protects boar sperm in vitro via its antioxidant capacity

The objective of the present study was to elucidate whether resveratrol could facilitate the survival of boar sperm during liquid preservation and fast cooling processes. Boar semen were diluted with Modena extender containing different concentrations of resveratrol. Sperm motility was evaluated by visual estimation. Membrane integrity, acrosome integrity and mitochondrial membrane potentials were measured by SYBR-14/PI, FITC-PNA and JC-1 staining, respectively. Moreover, the levels of reactive oxygen species (ROS), malonaldehyde (MDA) and total antioxidant capacity (T-AOC) were measured using commercial assay kits. B-cell lymphoma protein-2 (BCL2) content was determined by western blotting. During liquid preservation at 17oC, the addition of 50 μM resveratrol to the Modena extender significantly improved sperm motility, membrane integrity, acrosome integrity, and sperm mitochondrial membrane potentials. Similar results were also observed in the 150 μM resveratrol group during the fast cooling process. Furthermore, addition of resveratrol led to a decrease of ROS and MDA, and an increase in the content of T-AOC and BCL2. These observations suggest that addition of resveratrol to Modena extender protects boar sperm against oxidative stress. The optimal concentrations of resveratrol are 50 μM and 150 μM during liquid preservation and fast cooling process, respectively.

A machine learning-driven study indicates emodin improves cardiac hypertrophy by modulation of mitochondrial SIRT3 signaling

Cardiac hypertrophy (CH) is an enormous risk factor in the process of heart failure development, however, there is still lack of effective treatment for CH. Mitochondrial protection is an effective way against CH. Rheum palmatum L. (rhubarb) has been used to treat chronic heart diseases such as heart failure, especially to inhibit cardiac compensatory enlargement. The aim of this study was to explore the pharmacodynamic component of rhubarb and reveal its pharmacological effects and targets in the treatment of CH. Based on network pharmacology and machine learning approach, ingredients of rhubarb and targets for CH were extracted and surflex docking was conducted for obtaining the optimal ingredient-target combination(s) and emodin-SIRT3 was identified for further functional analysis. Transverse aortic constriction or isoproterenol induced CH mice and phenylephrine injured cardiomyocytes were used to verify the mitochondria protection effect and CH improvement of emodin in vivo and in vitro by modulation of mitochondrial SIRT3 signaling. The results showed that emodin could block agonist-induced and pressure overload-mediated CH. Emodin prevented mitochondrial dysfunction and its underlying mechanism was attributed to the activation of SIRT3, but the effect was not obvious with the presence of SIRT3 inhibitors (3-TYP)/SIRT3 siRNA. Furthermore, PGC-1ɑ was involved in the process of emodin regulating SIRT3 signaling pathway as an upstream target. Our findings clarified the main material basis and mechanism of rhubarb in the treatment of CH. Emodin, as the major ingredient of rhubarb, has therapeutic potential for CH through mitochondrial protection due to the modulation of SIRT3 signaling.

Transient scrotal hyperthermia affects human sperm DNA integrity, sperm apoptosis, and sperm protein expression

This prospective randomized clinical study is aimed to evidence the reproductive impairment of frequent scrotal heat exposure. A total of 20 normozoospermic subjects were randomly divided into two groups to undergo testicular warming in a 43 °C water bath 10 times, for 30 min each time; the subjects in group 1 underwent testicular warming for 10 consecutive days and those in group 2 once every 3 days. Sperm chromatin structure assay (SCSA), sperm mitochondrial membrane potential (MMP), apoptosis, and seminal plasma-soluble Fas (sFas) were analyzed before treatment and every 2 weeks after, for a total of 10 times. In group 1, some critical proteins involved in heat stress, hypoxia, structure, and function of sperm mitochondria and flagella were evaluated before hyperthermia and 2, 6, 10, and 16 weeks after hyperthermia. Both groups showed a reversible increase in the proportion of spermatozoa with a disrupted MMP (both p < 0.05 when the minimums were compared with baseline levels, the same below), sperm apoptosis (both p < 0.01) and high DNA stainability (both p < 0.05). The sFas concentration in both groups showed no obvious changes except one: the value at week 2 was significantly increased over baseline in group 1 (p = 0.036). The level of Bcl-2 decreased significantly at weeks 6 and 10 (p = 0.017 and 0.05, respectively) and recovered to baseline at week 16. Proteins involved in heat stress and mitochondria functions were up-regulated, whereas in flagella structure and function was down-regulated (all p < 0.05). This study demonstrated that transient and frequent scrotal hyperthermia severely and reversibly damaged spermatogenesis, consecutive heat exposure had more serious effects than intermittent exposure, whereas intermittent exposure led to a later recovery of sperm damage.

Vitamin E Analogue Improves Rabbit Sperm Quality during the Process of Cryopreservation through Its Antioxidative Action

The process of cryopreservation results in high concentration of reactive oxygen species which is detrimental to spermatozoa. The aim of this study was to investigate whether addition of vitamin E analogue to freezing extender can facilitate the cryosurvival of spermatozoa in rabbits, and how vitamin E protects spermatozoa against damages during the process of preservation. Freshly ejaculated semen was diluted with Tris-citrate-glucose extender supplemented with different concentrations of Trolox (a vitamin E analogue). The level of radical oxygen species (ROS) in spermatozoa that was exposed to Trolox was significantly lower than that of the control during each step of the process of preservation. The percentage of frozen-thawed spermatozoa with lipid peroxidation in the Trolox treatments was significantly lower than that of the control. The motility, intact acrosome, membrane integrity and mitochondrial potentials of the frozen-thawed spermatozoa in the treatment of 200 μM Trolox were significantly higher than those of the control. These observations suggest that addition of vitamin E to a freezing extender leads to higher integrity of acrosome, plasma membrane and mitochondrial membrane potential as well as higher motility. Vitamin E protects spermatozoa through its capacity to quench ROS accumulation and lipid peroxidation during the process of preservation. Addition of Trolox is recommended to facilitate the improvement of semen preservation for the rabbit breeding industry.

Mitochondrial fusion/fission process involved in the improvement of catalpol on high glucose-induced hepatic mitochondrial dysfunction

Catalpol, an iridoid glycoside, has been shown to exert hypoglycemic effect by rescuing mitochondrial function, but the detailed mechanism remains unclear yet. In this study, the effect and mechanism of catalpol on the hepatic mitochondria under diabetic conditions were further examined. Oral administration of catalpol significantly reduced the blood glucose, triglyceride, and cholesterol levels in high-fat diet- and streptozotocin-induced diabetic mice. Additionally, catalpol attenuated the decrease in liver mitochondrial ATP content resulting from diabetes. Furthermore, the number of mitochondria possessing a long size was increased in catalpol-treated mice. Interestingly, the catalpol-induced recovery of mitochondrial function was associated with decreased fission protein 1 and dynamin-related protein 1 expression as well as increased mitofusin 1 expression in the liver. In HepG2 cells, catalpol alleviated the decrease of ATP content and mitochondrial membrane potential, and the increase of reactive oxygen species formation induced by high glucose. MitoTracker Green stain shows that the tubular feature of mitochondria was maintained when cells were treated with catalpol. Catalpol also decreased fission protein 1 and dynamin-related protein 1 expression and increased mitofusin 1 expression in HepG2 cells. The present results suggest that catalpol can ameliorate hepatic mitochondrial dysfunction under a diabetic state, and this may be related to its regulation of mitochondrial fusion and fission events.

Andrographolide sodium bisulfate-induced apoptosis and autophagy in human proximal tubular endothelial cells is a ROS-mediated pathway

BACKGROUND AND AIMS

The nephrotoxic mechanisms of andrographolide sodium bisulfate (ASB) remain largely unknown. This study attempted to explore the mechanism of ASB-induced nephrotoxicity using human proximal tubular endothelial cells (HK-2).

METHODS

For this study HK-2 cells were treated with rising concentrations of ASB. Their survival rate was detected using MTT assay and ultrastructure was observed with electron microscopy. L-Lactate dehydrogenase (LDH) assay was followed by examination of mitochondrial membrane potential (MMP). Reactive oxygen species (ROS) was detected using different methods and apoptosis/autophage related proteins were detected using immunoblotting.

RESULTS

We found that ASB inhibited HK-2 cell proliferation and decreased cell survival rate in a time and dose-dependent manner (P<0.05, P<0.01, respectively). With increasing ASB concentration, cell structure was variably damaged and evidence of apoptosis and autophagy were observed. MMP gradually decreased and ROS was induced. The expression of JNK and Beclin-1 increased and activation of the JNK signaling pathway were seen. Apoptosis was induced via the mitochondrial-dependent caspase-3 and caspase-9 pathway, and autophagy related protein Beclin-1 was enhanced by ASB.

CONCLUSION

The data show that ASB induces high levels of ROS generation in HK-2 cells and activates JNK signaling. Furthermore, ASB induces cell apoptosis via the caspase-dependent mitochondrial pathway, and induces cellular autophagy, in part by enhancing Beclin-1 protein expression.

An effective solution to discover synergistic drugs for anti-cerebral ischemia from traditional Chinese medicinal formulae

Recently, the pharmaceutical industry has shifted to pursuing combination therapies that comprise more than one active ingredient. Interestingly, combination therapies have been used for more than 2500 years in traditional Chinese medicine (TCM). Understanding optimal proportions and synergistic mechanisms of multi-component drugs are critical for developing novel strategies to combat complex diseases. A new multi-objective optimization algorithm based on least angle regression-partial least squares was proposed to construct the predictive model to evaluate the synergistic effect of the three components of a novel combination drug Yi-qi-jie-du formula (YJ), which came from clinical TCM prescription for the treatment of encephalopathy. Optimal proportion of the three components, ginsenosides (G), berberine (B) and jasminoidin (J) was determined via particle swarm optimum. Furthermore, the combination mechanisms were interpreted using PLS VIP and principal components analysis. The results showed that YJ had optimal proportion 3(G): 2(B): 0.5(J), and it yielded synergy in the treatment of rats impaired by middle cerebral artery occlusion induced focal cerebral ischemia. YJ with optimal proportion had good pharmacological effects on acute ischemic stroke. The mechanisms study demonstrated that the combination of G, B and J could exhibit the strongest synergistic effect. J might play an indispensable role in the formula, especially when combined with B for the acute stage of stroke. All these data in this study suggested that in the treatment of acute ischemic stroke, besides restoring blood supply and protecting easily damaged cells in the area of the ischemic penumbra as early as possible, we should pay more attention to the removal of the toxic metabolites at the same time. Mathematical system modeling may be an essential tool for the analysis of the complex pharmacological effects of multi-component drug. The powerful mathematical analysis method could greatly improve the efficiency in finding new combination drug from TCM.

By improving regional cortical blood flow, attenuating mitochondrial dysfunction and sequential apoptosis galangin acts as a potential neuroprotective agent after acute ischemic stroke

Ischemic stroke is a devastating disease with a complex pathophysiology. Galangin is a natural flavonoid isolated from the rhizome of Alpina officinarum Hance, which has been widely used as an antioxidant agent. However, its effects against ischemic stroke have not been reported and its related neuroprotective mechanism has not really been explored. In this study, neurological behavior, cerebral infarct volumes and the improvement of the regional cortical blood flow (rCBF) were used to evaluate the therapeutic effect of galangin in rats impaired by middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia. Furthermore, the determination of mitochondrial function and Western blot of apoptosis-related proteins were performed to interpret the neuroprotective mechanism of galangin. The results showed that galangin alleviated the neurologic impairments, reduced cerebral infarct at 24 h after MCAO and exerted a protective effect on the mitochondria with decreased production of mitochondrial reactive oxygen species (ROS). These effects were consistent with improvements in the membrane potential level (Dym), membrane fluidity, and degree of mitochondrial swelling in a dose-dependent manner. Moreover, galangin significantly improved the reduced rCBF after MCAO. Western blot analysis revealed that galangin also inhibited apoptosis in a dose-dependent manner concomitant with the up-regulation of Bcl-2 expression, down-regulation of Bax expression and the Bax/Bcl-2 ratio, a reduction in cytochrome c release from the mitochondria to the cytosol, the reduced expression of activated caspase-3 and the cleavage of poly(ADP-ribose) polymerase (PARP). All these data in this study demonstrated that galangin might have therapeutic potential for ischemic stroke and play its protective role through the improvement in rCBF, mitochondrial protection and inhibiting caspase-dependent mitochondrial cell death pathway for the first time.