Ciprofloxacin and enrofloxacin can cause reproductive toxicity via endocrine signaling pathways

Ciprofloxacin (CIP) and enrofloxacin (ENR) are veterinary antibiotics commonly utilized to treat and prevent animal diseases. Environmental and dietary antibiotic residues can directly and indirectly affect the reproductive development of animals and humans. This article investigated the reproductive toxicity of CIP in male zebrafish, showing that it could decrease the spermatogonial weight and damage the spermatogonial tissue. The sex hormone assays showed that CIP decreased fshb and lhb gene expression and plasma testosterone (T). In addition, transcriptome analysis indicated that the effect of CIP on zebrafish might be related to the endocrine signaling pathways. ENR, which was selected for further study, inhibited mouse Leydig (TM3) and Sertoli (TM4) cell proliferation and caused cell cycle arrest. The sperm concentration, serum luteotropic hormone (LH) and follicle-stimulating hormone (FSH), and T levels decreased in adolescent mice after ENR treatment for 30d in vivo. Hematoxylin and eosin (H&E) staining showed that ENR exposure potentially induced testicular injury, while the real-time quantitative PCR (qPCR) results indicated that ENR inhibited the mRNA expression of key genes in the Leydig cells (cyp11a1, 3β-HSD, and 17β-HSD), Sertoli cells (Inhbβ and Gdnf) and spermatogenic cells (Plzf, Stra8 and Dmc1). In conclusion, these findings indicated that ENR exposure might influence the development of the testes of pubescent mice.

Role of Doxorubicin on the Loading Efficiency of ICG within Silk Fibroin Nanoparticles

The effective loading or encapsulation of multimodal theranostic agents within a nanocarrier system plays an important role in the clinical development of cancer therapy. In recent years, the silk fibroin protein-based delivery system has been drawing significant attention to be used in nanomedicines due to its biocompatible and biodegradable nature. In this study, silk fibroin nanoparticles (SNPs) have been synthesized by a novel and cost-effective ultrasonic atomizer-based technique for the first time. The fabricated SNPs were coencapsulated by the FDA-approved indocyanine green (ICG) dye and the chemotherapeutic drug doxorubicin (DOX). The synthesized SNPs are spherical, with an average diameter of ∼37 ± 4 nm, and the ICG-DOX-coencapsulated SNPs (ID-SNPs) have a diameter size of ∼47 ± 6 nm. For the first time, here we demonstrate that DOX helps in the higher loading of ICG within the ID-SNPs, which enhances the encapsulation efficiency of ICG by ∼99%. This could be attributed to the interaction of ICG and DOX molecules with the silk fibroin protein, which helps ICG to get loaded more efficiently within these nanoparticles. The overall finding of this study suggests that the ID-SNPs could be utilized for enhanced ICG-complemented multimodal deep-tissue bioimaging and synergistic chemo-photothermal therapy.

Antibiotic toxicity on human spermatozoa assessed using the sperm DNA fragmentation dynamic assay

Sperm DNA fragmentation (SDF) dynamic assays were piloted on 4 fresh ejaculates to examine the possible sperm toxicity of three common antibiotics, ciprofloxacin, doxycycline and ampicillin, incubated at a concentration estimated to be reached in semen in vivo, and 100×, for 24 h. SDF was assessed in terms of single-strand DNA breaks (SSBs) and double-strand DNA breaks (DSBs). Low and high concentrations of ciprofloxacin and high concentration of doxycycline significantly increased the SDF rate, due to sperm containing SSBs. Ampicillin did not affect SDF dynamics at any dose. Based on these results, the effect of antibiotics on the global-SDF dynamics was further examined in 21 ejaculates assessed at 0, 4 and 6 h. Ciprofloxacin increased the rate of SDF at the low concentration in 17 from 21 subjects; the high concentration resulted in a stronger effect in all individuals. A significant increase in the rate of SDF in 17 ejaculates was also noted when spermatozoa were incubated with the high concentration of doxycycline. The dynamic SDF assay is a rapid and sensitive tool to evidence sperm toxicity. Ciprofloxacin should be avoided when it is necessary to preserve sperm quality for reproductive purposes and as additive in semen diluents.

A systems toxicology approach to explore toxicological mechanisms of fluoroquinolones-induced testis injury

The widespread use of fluoroquinolones (FQs) causes a serious risk to the environment and human health. Here, we evaluated the potential effect to induce testis damage by gatifloxacin (GAT) intragastrically treatment in mice (25, 50, and 100 mg/kg body weight per day for 7 days). We observed testicular weight, serum testosterone, antioxidant enzyme activity, and mRNA levels and pathways. Testicular histopathology indicated that GAT administration induced a dose-dependent spermatogenesis abnormality. At 50 mg/kg, GAT altered gene expression but did not change the weight and the levels of testosterone and antioxidant enzymes. These findings indicate that mRNA levels are more sensitive than weight and testosterone for detecting GAT testicular toxicity. We also found that GAT induced testicular damage by regulating the candidate genes associated with spermatogenesis, germ cell movement, testicular fibrosis, and reproductive axis development. This study enhances our perception of the mechanism of FQs-induced testicular toxicity and environmental effects. However, the molecular mechanism needs to be further researched.

Rosuvastatin and low-dose carvedilol combination protects against isoprenaline-induced myocardial infarction in rats: Role of PI3K/Akt/Nrf2/HO-1 signalling

Rosuvastatin has been shown to activate PI3K/Akt/Nrf2/HO-1 pathway, which promotes cell survival in the myocardium. This study investigated the therapeutic benefit of adding rosuvastatin to low-dose carvedilol in protection against myocardial infarction (MI). Rosuvastatin (RSV) and carvedilol (CAR) were given for 7 consecutive days with concurrent administration of two doses of isoprenaline (ISP) on 6th and 7th days to induce MI. Isoprenaline injections caused detrimental alterations in the myocardial architecture and electrocardiogram (ECG) pattern and significantly increased the infarct size, heart index and serum levels of cardiotoxicity markers compared to the control group. ISP induced oxidative damage, inflammatory and apoptotic events and downregulated PI3K/Akt/Nrf2/HO-1 signalling pathway compared to the control values. Treatment with low-dose CAR and/or RSV prevented the ECG and histopathological alterations induced by ISP, and also reduced the infarct size, heart index, serum creatine kinase-MB, cardiac troponin-I and C-reactive protein levels compared to ISP group. CAR and/or RSV treatment restored the activity of superoxide dismutase and total antioxidant capacity with a consequent reduction in lipid peroxides level. Further, they decreased the expression of nuclear factor (NF)-κB (p65) and increased the phosphorylated PI3K and Akt, which may activate the anti-apoptotic signalling as evidenced by the decreased active caspase 3 level. The combination therapy has a more significant effect in the most studied parameters than their monotherapy, which may be because of the activation of PI3K/Akt Nrf2/HO-1 pro-survival signalling pathway. This study highlights the potential benefits of combining RSV with low-dose CAR in case of MI.

The MTT assay application to measure the viability of spermatozoa: A variety of the assay protocols

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay is one of the methods used to evaluate the viability of sperm. In the assay, a tetrazolium component (MTT) is converted into MTT formazan by some specific enzymes in the viable cells. The amount of formazan product in theory is directly correlated with the percentage of viable sperms. It is quantified by measuring the absorbance using a spectrophotometer. The present article compiles the MTT assays that have been used to determine sperm viability in most animal species and humans. In each assay, other factors apart from the number of viable cells that potentially influence the accuracy and precision of results are stated, such as preparations of sperm and MTT solutions, length and conditions of incubation, and a solubilizing agent as well as the formazan detection method. Also, the strengths and shortcomings of the MTT test comparison with the others are summarized at the end of this article. This information may be useful for prospective researchers deciding to implement this colorimetric method in their experiments.

CXCL8, overexpressed in colorectal cancer, enhances the resistance of colorectal cancer cells to anoikis

Anoikis is a form of apoptosis which occurs when anchorage-dependent cells either show loss of adhesion or inappropriate adhesion. Only a few cancer cells that detach from the primary site of the tumor acquire the ability to resist anoikis and form metastasis. The mechanism underlying the resistance of colorectal cancer (CRC) cells to anoikis remains unclear. Interleukin-8 (alternatively known as CXCL8) is associated with CRC angiogenesis and progression. Here, we found that a high abundance of CXCL8 or TOPK strongly correlated with poor overall and disease-free survival of 186 patients with CRC. A combination of high CXCL8 and high TOPK expressions had the worst prognosis. We showed that CXCL8 expression was negatively correlated with anoikis in CRC cells. CXCL8 treatment enhanced the resistance of CRC cells to apoptosis, which was accompanied by the increase of TOPK, and the activation of AKT and ERK. Moreover, we demonstrated that the inhibition of either ERK or AKT by specific chemical inhibitors attenuated the CXCL8-mediated resistance to anoikis. Treatment with AKT inhibitor abolished the effects of CXCL8 on TOPK expression, suggesting that TOPK was downstream of AKT in the process of anoikis. Taken together, we demonstrated that CXCL8 is strongly implicated in the resistance of CRC cells to anoikis, and that the AKT, TOPK and ERK pathway may be a potential therapeutic target for CRC.

Acetylproteomic analysis reveals functional implications of lysine acetylation in human spermatozoa (sperm)

Male infertility is a medical condition that has been on the rise globally. Lysine acetylation of human sperm, an essential posttranslational modification involved in the etiology of sperm abnormality, is not fully understood. Therefore, we first generated a qualified pan-anti-acetyllysine monoclonal antibody to characterize the global lysine acetylation of uncapacitated normal human sperm with a proteomics approach. With high enrichment ratios that were up to 31%, 973 lysine-acetylated sites that matched to 456 human sperm proteins, including 671 novel lysine acetylation sites and 205 novel lysine-acetylated proteins, were identified. These proteins exhibited conserved motifs XXXKYXXX, XXXKFXXX, and XXXKHXXX, were annotated to function in multiple metabolic processes, and were localized predominantly in the mitochondrion and cytoplasmic fractions. Between the uncapacitated and capacitated sperm, different acetylation profiles in regard to functional proteins involved in sperm capacitation, sperm-egg recognition, sperm-egg plasma fusion, and fertilization were observed, indicating that acetylation of functional proteins may be required during sperm capacitation. Bioinformatics analysis revealed association of acetylated proteins with diseases and drugs. Novel acetylation of voltage-dependent anion channel proteins was also found. With clinical sperm samples, we observed differed lysine acetyltransferases and lysine deacetylases expression between normal sperm and abnormal sperm of asthenospermia or necrospermia. Furthermore, with sperm samples impaired by epigallocatechin gallate to mimic asthenospermia, we observed that inhibition of sperm motility was partly through the blockade of voltage-dependent anion channel 2 Lys-74 acetylation combined with reduced ATP levels and mitochondrial membrane potential. Taken together, we obtained a qualified pan-anti-acetyllysine monoclonal antibody, analyzed the acetylproteome of uncapacitated human sperm, and revealed associations between functional protein acetylation and sperm functions.