Leukocyte populations in peripheral blood of dromedary camels with clinical endometritis

Serum cortisol level as marker of stress in camels: relationship with immunological profile

The present study evaluated serum cortisol levels as a stress indicator in camels and analyzed the influence of some physiological and pathological factors on cortisol levels and their relationship with immunological parameters. A total number of 169 camels (Camelus dromedarius) were grouped in a healthy group (n = 106 camels), a slaughterhouse group (n = 20 camels), a Surra-affected group (n = 27 camels), and a metritis-affected group (n = 16 camels). Female camels exhibited higher cortisol levels compared to males, with non-pregnant and lactating she-camels showing elevated levels relative to their pregnant and non-lactating counterparts. No significant differences in cortisol levels were observed among camel breeds (Majaheem, Magateer, Sawahli, and Omani). Elevated cortisol levels were observed in stressed camels (pre-slaughter) and diseased camels, including those with Surra and bacterial metritis, confirming the reliability of cortisol as a stress marker in this species. Increased cortisol levels were associated with leukocytosis, neutrophilia, and a higher neutrophil-to-lymphocyte ratio. Phenotypically, elevated cortisol level was associated with an expanded CD4 T-cell population, reduced γδ T cells percentage, decreased CD172a expression on neutrophils and monocytes, reduced CD14 and CD163 expression on monocytes, and enhanced CD45 and MHC I expression on lymphocytes. Functionally, higher cortisol levels were linked to increased reactive oxygen species (ROS) production in blood phagocytes. These findings highlight the modulatory effects of cortisol on the camel immune system and emphasize the importance of considering gender and reproductive status when evaluating stress in camels.

Leonurine Exerts Anti-Inflammatory Effects in Lipopolysaccharide (LPS)-Induced Endometritis by Modulating Mouse JAK-STAT/PI3K-Akt/PPAR Signaling Pathways

Endometritis is a common disease in postpartum cows, characterized by delayed uterine recovery due to endometrial inflammation. Although antibiotics and hormones are commonly used, they have certain limitations. One potential alternative is using motherwort extract, specifically leonurine, which exhibits anti-inflammatory properties. However, leonurine's exact molecular mechanism of action remains unclear. In this study, 40 mice were randomly divided into four groups: a control group, endometritis model group, LPS + leonurine group (30 mg/kg), and LPS + dexamethasone group (5 mg/kg). Transcriptomic analysis revealed that leonurine modulates multiple signaling pathways, including JAK-STAT/PI3K-Akt, and influences the expression of key genes, such as Prlr, Socs2, Col1a1, and Akt1. Furthermore, leonurine effectively reduces levels of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-1β (p < 0.01), which play a crucial role in regulating acute endometritis. Additionally, leonurine helps maintain cholesterol homeostasis and attenuates inflammation through the peroxisome proliferator-activated receptor (PPAR) signaling pathway by modulating genes such as Cyp27a1, Hmgcs1, and Scd2. These findings suggest that leonurine has a protective effect against LPS-induced endometritis and that its anti-inflammatory properties involve multiple pathways and targets, which are potentially mediated by regulating signaling pathways such as JAK-STAT/PI3K-Akt and PPAR.

Clinical and subclinical endometritis in dromedary camels: An overview of definition and clinical presentation, etiopathogenesis, diagnostic biomarkers, and treatment protocols

The current review collected and analyzed research on clinical endometritis (CE) and subclinical endometritis (SCE) in dromedary camels in terms of definition and clinical presentation, etiopathogenesis, diagnostic biomarkers, and treatment protocols. CE is characterized by uterine inflammation with abnormal vaginal discharges, while SCE comprises uterine inflammation with no clinical signs and is described as the infiltration of polymorphnuclear cells into the endometrium. CE is the prevalent clinical finding of barren female dromedaries (18-60 %). SCE has been detected in 9.9 % of infertile female dromedaries. CE and SCE are observed mainly in repeat breeding females. Unhygienic reproductive management, unsanitary dealings during parturition, and postpartum problems are major risk factors. Environmental stress, immunodeficiency, mucus abrasion, or the presence of other opportunistic microbes are predisposing factors. Trueperella pyogenes, Escherichia coli, Pseudomonas aeruginosa, Streptococcus spp., and Staphylococcus spp. are the major uterine isolates obtained from females with CE, while Bacillus spp., Staphylococcus spp., and Candida albicans are the most frequent isolates of SCE. CE and SCE reveal biomarker changes that could aid in the diagnosis of this common reproductive disorder. Only a few treatment protocols for CE and SCE have been tried and proven to work in camel practice. However, there is room for the new, challenging treatment programs proposed in this review. This review also provides a compilation that may be of use to future research and to those working in the field of camel reproduction.

Efficacy of different treatment protocols for endometritis in Camelus dromedarius

Endometritis is considered a significant cause of infertility problems in dromedary camels. This study aimed to compare the efficacy of different treatment protocols for endometritis in dromedary camels under Abu Dhabi Emirates' conditions. A total of 112 dromedary she-camels with uterine infection were subjected to uterine swabbing for bacterial culture and received one of the following treatments: (i) uterine douching with lotagen every other day for three doses, (ii) single parenteral oxytetracycline injection, (iii) subcutaneous injection with ceftiofur for 5 days, or (vi) combined oxytetracycline-ceftiofur injection. The results showed that Escherichia coli was the most isolated bacteria, followed by Streptococcus species. Treatment efficacy was (P < 0.05) higher in ceftiofur and oxytetracycline-ceftiofur protocols compared with lotagen and oxytetracycline protocols. The fertility indexes, services per conception and pregnancy rate, were improved in ceftiofur and mixed oxytetracycline plus ceftiofur protocols as the pregnancy rate was (P < 0.05) higher in those protocols compared with lotagen and oxytetracycline protocols (71.4 and 67.9% vs. 39.3 and 42.9%, respectively). On the other hand, the number of services per conception was significantly lower in ceftiofur and oxytetracycline-ceftiofur protocols (1.2 for each protocol) than in lotagen and oxytetracycline protocols (1.8 and 1.7, respectively). In conclusion, subcutaneous injection of 1 ml ceftiofur per 50 kg body mass for 5 days can be used as an efficient treatment for uterine infection in female dromedary camels caused by E. coli and Streptococcus species for improving their fertility indexes.

Bacterial species-specific modulatory effects on phenotype and function of camel blood leukocytes

Background

Recent studies have reported pathogen-species-specific modulating effects on the innate immune system. Escherichia coli, Staphylococcus aureus, and Streptococcus agalactiae are important pathogenic bacteria responsible for different infectious diseases in several animal species. In the present study, a whole blood culture with S. aureus, E. coli, or S. agalactiae and flow cytometry were used to investigate, whether stimulation with different bacterial species induces different immunomodulation patterns in camel leukocytes. The expression of different cell surface myeloid markers and cell adhesion molecules on monocytes and neutrophils was investigated. In addition, the capacity of monocytes and neutrophils to produce reactive oxygen species (ROS) was analyzed.

Results

Stimulation with either of the bacterial species resulted in the expansion of the camel CD14^highMHCII^high monocyte subset with a reduced fraction of CD14^highMHCII^low monocytes. For the CD14^lowMHCII^high monocytes, however, only stimulation with S. aureus or S. agalactiae increased their fractions in blood. Although all bacterial species elicited the upregulation of cell surface MHC class II molecules on granulocytes, the increase was, however, highest on cells stimulated with S. aureus. The expression levels of the two adhesion molecules, CD11a and CD18, on neutrophils and monocytes were differently affected by bacterial stimulation. Functionally, E. coli failed to stimulate ROS production in monocytes, while induced a strong ROS production response in granulocytes. S. agalactiae elicited a week ROS production in granulocytes when compared to the other two pathogens.

Conclusions

The different responsiveness of monocytes and granulocytes toward different bacterial species indicates different host-pathogen interaction mechanisms for the two cell populations. In addition, the phenotypic and functional differences between cells stimulated with E. coli, S. aureus, or S. agalactiae suggests pathogen-species-specific modulating effects of the bacterial pathogens on the camel innate myeloid cells.

Recent Advances in Camel Immunology

Camels are domesticated animals that are highly adapted to the extreme desert ecosystem with relatively higher resistance to a wide range of pathogens compared to many other species from the same geographical region. Recently, there has been increased interest in the field of camel immunology. As the progress in the analysis of camel immunoglobulins has previously been covered in many recent reviews, this review intends to summarize published findings related to camel cellular immunology with a focus on the phenotype and functionality of camel leukocyte subpopulations. The review also describes the impact of different physiological (age and pregnancy) and pathological (e.g. infection) conditions on camel immune cells. Despite the progress achieved in the field of camel immunology, there are gaps in our complete understanding of the camel immune system. Questions remain regarding innate recognition mechanisms, the functional characterization of antigen-presenting cells, and the characterization of camel NK and cytotoxic T cells.