Azithromycin Treatment Modulates Cytokine Production inChlamydia trachomatisInfected Women

Combination of kaempferol and azithromycin attenuates Staphylococcus aureus-induced osteomyelitis via anti-biofilm effects and by inhibiting the phosphorylation of ERK1/2 and SAPK

Osteomyelitis is bacterial infection of bone, commonly caused by Staphylococcus aureus. This work aims to study the potential of azithromycin and kaempferol against chronic osteomyelitis induced by azithromycin-resistant Staphylococcus aureus (ARSA). It was noticed that rats tolerated the treatments with no diarrhoea or weight loss; also, no deaths were observed in rats. The treatment by azithromycin alone failed to inhibit bacterial growth and also had no effect on the infection condition of bone, although the treatment decreased the levels of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α), but did not improve the oxidative stress levels. Kaempferol monotherapy slightly inhibited bacterial growth and bone infection; the treatment also inhibited the levels of IL-6 and (TNF-α). The treatment also improved the antioxidant status. However, the combined treatment of azithromycin and kaempferol significantly suppressed bacterial growth and bone infection and modulated oxidative stress. In vitro, the combined treatment inhibited the levels of IL-6 and TNF-α, and also suppressed the phosphorylation of ERK1/2 and stress-activated protein kinase (SAPK). The combined treatment also showed anti-biofilm activity in ARSA. The combination attenuates ARSA-induced osteomyelitis in rats compared with their treatments alone by reducing oxidative stress, inhibiting the phosphorylation of ERK1/2 and SAPK and inhibiting biofilm formation.

Upregulation of FOXP3 is associated with severity of hypoxia and poor outcomes in COVID-19 patients

The levels of messenger RNA (mRNA) transcription of FOXP3, IFN-γ, TNF, IL-6 and COX-2 from both COVID-19 infected and control subjects were evaluated using SYBR^TM green real-time polymerase chain reaction (RT-PCR). Severe/critical cases showed significantly lower lymphocyte counts and higher neutrophil counts than the mild or moderate cases. There were significantly lower levels of mRNA expressions of IFN-γ, TNFα and FOXP3 in COVID-19 patients than in the control group. On the other hand, IL-6 and COX-2 expressions were significantly higher in patients suffering from severe disease. FOXP3 expressions were correlated with the severities of hypoxia and were excellent in predicting the disease severity. This was followed by the IL-6, COX-2 and TNFα expressions. FOXP3 expression was the only biomarker to show a significant correlation with patient mortality. It was concluded that SARS-CoV-2 infection is associated with the downregulation of FOXP3 and upregulations of IL-6 and COX-2.

HIV susceptibility in women: The roles of genital inflammation, sexually transmitted infections and the genital microbiome

Given that heterosexual transmission of HIV across the genital mucosa is the most common route of infection in women, an in-depth understanding of the biological mechanisms associated with HIV risk in the female genital tract (FGT) is essential for effective control of the epidemic. Genital pro-inflammatory cytokines are well-described biological co-factors to HIV risk. Increased levels of pro-inflammatory cytokines in the FGT have been associated with a 3-fold higher-risk of acquiring HIV, presumably through involvement in barrier compromise and the recruitment of highly activated HIV target cells to the site of initial viral infection and replication. Sexually transmitted infections (STIs) and bacterial vaginosis (BV) are suggested possible contributors to genital inflammation in the FGT, and this, coupled with the relationship between genital inflammation and HIV risk, underscores the importance of effective treatment of STI and BV in the promotion of women's health. In most low- and middle-income countries, STIs are treated syndromically, a practice providing rapid treatment without identifying the infection source. However, this approach has been associated with over-diagnosis and the overuse of drugs. Further, because many women with STIs are asymptomatic, syndromic management also fails to treat a vast proportion of infected women. Although several studies have explored the role of STIs and the vaginal microbiome on genital inflammation and HIV risk, the impact of STI and BV management on genital inflammation remains poorly understood. This review aimed to collate the evidence on how BV and STI management efforts affect genital inflammation and the genital microbiome in women.

A European perspective on topical ophthalmic antibiotics: current and evolving options

BACKGROUND

Eye infections can be vision-threatening and must be treated effectively by appropriate and safe use of topical ophthalmic anti-infectives. This review will essentially consider the current and evolving treatment options for the various types of bacterial eye infections. Ocular surface bacterial infections affect subjects of all ages with a high frequency in newborns and children.

METHODS

This article presents a review of the peer-reviewed published scientific literature in order to define the well-established uses of anti-infective eye drops in the field of ocular infections. A comprehensive search of the recent published literature including topical ophthalmic anti-infectives effective in bacterial ocular infections was performed. Clinical studies provide relevant data concerning the characteristics and clinical efficacy of antibacterial eye drops in ocular anterior segment infections or for perioperative prophylaxis. Publications were included to cover the current options of antibacterial eye drops available in Europe.

RESULTS

Several recent publications identified effective topical ocular antibacterials requiring a reduced dose regimen and a short treatment course. Additional literature reviewed included data on novel perioperative prophylaxis, indications for topical fortified antibiotics and innovative research including the risk of resistance.

CONCLUSIONS

Safe and effective topical antibiotic eye drops for the treatment and prevention of ocular infections must be adapted to the type of bacteria suspected. Usual topical antimicrobials should be replaced by more recent and more effective treatments. The use of highly effective fluoroquinolones should be reserved for the most severe cases to avoid resistance. Short treatment courses, such as azithromycin, can be easily used in children, thereby improving quality of life.

Differing effects of azithromycin and doxycycline on cytokines in cells from Chlamydia trachomatis-infected women

Chlamydial infection of the lower genital tract usually spreads to the upper genital tract and is then responsible for more serious consequences, such as infertility, ectopic pregnancy, pelvic pain, and pelvic inflammatory disease. Genital infection with Chlamydia trachomatis and the resulting cytokine response largely determines the outcome of infection and disease. To date, studies showing comparative effects of azithromycin and doxycycline treatment for C. trachomatis infection in women with reproductive sequelae like infertility and their effect on immune molecules like cytokines are lacking. Hence, our objective was to study the effect of azithromycin and doxycycline in vitro on cytokines in cells from C. trachomatis-positive fertile and infertile women as well as their efficacy in C. trachomatis infection. Fertile and infertile women with primary and recurrent C. trachomatis infection attending the gynecology outpatient department of Safdarjung Hospital, New Delhi, India, were enrolled. Enzyme-linked immunosorbent assay and real-time reverse transcription-polymerase chain reaction was performed for evaluating cytokines in cells stimulated with chlamydial elementary bodies (EBs) in the presence and absence of antibiotics (azithromycin and doxycycline). C. trachomatis-infected women were also followed up to assess the efficacy of azithromycin and doxycycline. We observed inhibition of cytokines (interleukin [IL]-1beta (β), IL-6, IL-8, IL-10, and tumor necrosis factor-alpha) in the presence of azithromycin in EB-stimulated cells from both fertile and infertile women with primary and recurrent C. trachomatis infection. However, in presence of doxycycline, inhibition of cytokines (IL-1β and IL-6) was only observed in stimulated cells from fertile women with primary C. trachomatis infection. The clinical efficacy of azithromycin was also better than doxycycline in recurrent C. trachomatis infection in women with complications such as infertility. Overall, this study suggests that azithromycin treatment with broader immunomodulatory effects may be preferable to doxycycline for the treatment of recurrent C. trachomatis infection associated with infertility.

Impact of azithromycin resistance mutations on the virulence and fitness of Chlamydia caviae in guinea pigs

Azithromycin (AZM) is a major drug used in the treatment and prophylaxis of infections caused by Chlamydia, yet no significant clinical resistance has been reported for these obligate intracellular bacteria. Nevertheless, spontaneous AZM resistance (Azm(r)) arose in vitro at frequencies ranging from 3 x 10(-8) to 8 x 10(-10) for clonal isolates of Chlamydia caviae, which is a natural pathogen of guinea pigs. Sequencing of the unique 23S rRNA gene copy in 44 independent Azm(r) isolates identified single mutations at position A(2058) or A(2059) (Escherichia coli numbering system). While SP(6)AZ(1) (A(2058)C) and SP(6)AZ(2) (A(2059)C) Azm(r) mutants showed growth defects in cell culture and were less pathogenic in the guinea pig ocular infection model than in the parent SP(6), the three isogenic C. caviae isolates grew equally well in the animal. On the other hand, coinoculation of the C. caviae parent strain with one of the Azm(r) strains was detrimental for the mutant strain. This apparent lack of association between pathology and bacterial load in vivo showed that virulence of the two Azm(r) mutants of C. caviae was attenuated. While chlamydial growth in vitro reflects the ability of the bacteria to multiply in permissive cells, survival in the host is a balance between cellular multiplication and clearance by the host immune system. The obligate intracellular nature of Chlamydia may therefore limit emergence of resistance in vivo due to the strength of the immune response induced by the wild-type antibiotic-sensitive bacteria at the time of antibiotic treatment.