Fecal microbiota transplantation stimulates type 2 and tolerogenic immune responses in a mouse model

OBJECTIVES

Clostridioides difficile infection (CDI) is the leading hospital-acquired infection in North America. While previous work on fecal microbiota transplantation (FMT), a highly effective treatment for CDI, has focused on colonization resistance mounted against C. difficile by FMT-delivered commensals, the effects of FMT on host gene expression are relatively unexplored. This study aims to identify transcriptional changes associated with FMT, particularly changes associated with protective immune responses.

METHODS

Gene expression was assessed on day 2 and day 7 after FMT in mice after antibiotic-induced dysbiosis. Flow cytometry was also performed on colon and mesenteric lymph nodes at day 7 to investigate changes in immune cell populations.

RESULTS

FMT administration after antibiotic-induced dysbiosis successfully restored microbial alpha diversity to levels of donor mice by day 7 post-FMT. Bulk RNA sequencing of cecal tissue at day 2 identified immune genes, including both pro-inflammatory and Type 2 immune pathways as upregulated after FMT. RNA sequencing was repeated on day 7 post-FMT, and expression of these immune genes was decreased along with upregulation of genes associated with restoration of intestinal homeostasis. Immunoprofiling on day 7 identified increased colonic CD45+ immune cells that exhibited dampened Type 1 and heightened regulatory and Type 2 responses. These include an increased abundance of eosinophils, alternatively activated macrophages, Th2, and T regulatory cell populations.

CONCLUSION

These results highlight the impact of FMT on host gene expression, providing evidence that FMT restores intestinal homeostasis after antibiotic treatment and facilitates tolerogenic and Type 2 immune responses.

The impact of existing total anti-toxin B IgG immunity in outcomes of recurrent Clostridioides difficile infection

Late anti-toxin-B humoral immunity acquired after treatment is important for preventing recurrent Clostridioides difficile infection. We prospectively-measured anti-toxin-B IgG and neutralization titers at diagnosis as potential early predictors of recurrence. High anti-toxin-B-IgG/neutralizing antibodies were associated with short-lasting protection within 6-weeks, however, no difference in recurrence risk was observed by 90-days post-infection.

Ultrasound simulation training to meet the 2021 Royal College of Radiologists' curriculum for radiology trainees: South East London experience

AIM

To enhance ultrasound teaching delivery to radiology trainees using a simulation course matched to the 2021 Royal College of Radiologists (RCR) curriculum.

MATERIAL AND METHODS

An ultrasound simulation training course was designed for specialty trainees (ST) 1 in radiology, which was based on the 2021 RCR curriculum and covered the top ultrasound training priorities. The course was piloted initially on two occasions in a 1-day format to the August 2021 and the March 2022 ST1 intake trainees. Based on the feedback, a comprehensive 4-day course was developed and delivered between October and December 2022 for the August 2022 ST1 intake, funded by Health Education England. The outcomes measured were subjective trainee feedback using numerical scores and free text.

RESULTS

All King's College Hospital NHS Foundation Trust radiology ST1 trainees from the August 2021 to the August 2022 intake participated in ultrasound simulation training. The training matched the RCR curriculum and increased the trainees' confidence and competency in medical ultrasound.

CONCLUSIONS

Ultrasound simulation training can be successfully delivered to ST1 trainees to match the 2021 RCR curriculum and enhance training in medical ultrasound for radiologists.

Host Immunity and Immunization Strategies for Clostridioides difficile Infection

Clostridioides difficile infection (CDI) represents a significant challenge to public health. C. difficile-associated mortality and morbidity have led the U.S. CDC to designate it as an urgent threat. Moreover, recurrence or relapses can occur in up to a third of CDI patients, due in part to antibiotics being the primary treatment for CDI and the major cause of the disease. In this review, we summarize the current knowledge of innate immune responses, adaptive immune responses, and the link between innate and adaptive immune responses of the host against CDI. The other major determinants of CDI, such as C. difficile toxins, the host microbiota, and related treatments, are also described. Finally, we discuss the known therapeutic approaches and the current status of immunization strategies for CDI, which might help to bridge the knowledge gap in the generation of therapy against CDI.

Sphingosine-1-phosphate receptors 2 and 3 reprogram resting human macrophages into M1 phenotype following mycobacteria infection

Mycobacteria tuberculosis (M.tb) the causative agent for tuberculosis has been accredited for a high rate of morbidity and mortality worldwide. The rise in MDR and XDR cases has further created new obstacles in achieving the "End TB Strategy", which is aimed for 2035. In this article, we have demonstrated the potential of sphingosine-1-phosphate (S1P) analogs in providing an anti-mycobacterial effector response by altering macrophage polarity into M1. Among S1PR1 and S1PR3 analogs, S1PR2 analogs proficiently favor selective polarization of infected human macrophages into M1 phenotypes, marked by increased expression of M1 markers and decreased M2 markers. Furthermore, S1PR1-3 analogs treated macrophages were also able to decrease the secretion of anti-inflammatory cytokine IL-10 and can induce NO secretion in infected macrophages. Lastly, only S1PR2-3 analogs were able to restrict the growth of mycobacteria in human macrophages. Taken together our study reflects the potential of S1PR2-3 analogs in providing host defenses following mycobacterial infection by favoring M1 macrophage polarization.

Correlation between BMI, caries prevalence, and sugar-containing beverage intake in 6-10 year old children

Background:

The beverages containing sugar are proven risk factors for obesity and dental caries. Therefore, owing to the shared risk factors, an interrelationship is suspected between BMI, sugar beverage consumption, and dental caries in children.

Aims:

The present trial was carried out to assess the interrelationship between BMI, sugar beverage consumption, and dental caries in children aged 6–10 years.

Materials and Methods:

Eighty-six children within the age range of 6–10 years answered the health questionnaire. The BMI was calculated, intra-oral assessment was done, the frequency of sweetened beverage consumption was recorded, and the collected data were subjected to the statistical evaluation to formulate results.

Results:

On evaluation, a non-significant difference was observed in BMI levels in the four groups (P = 0.12). Whole-milk intake also showed an inverse correlation with dental caries and BMI, but this correlation was statistically non-significant with the respective values of P = 0.57 and 0.55. A similar inverse relationship was seen for low-fat milk for caries and BMI with P = 0.65 and 0.45, respectively. Regarding soft drinks, 44.1% (n = 38) took soft drinks, and a non-significant relation between caries and intake as well as BMI and intake with P = 0.86 and 0.55, respectively.

Conclusion:

Within its limitations, the present study concludes that no correlation exists between BMI and dental caries as well as between sugar-containing beverage consumption and dental caries. Also, BMI and sugar-containing beverage consumption showed no correlation in children aged 6–10 years.

Personalized therapy: can it tame the COVID-19 monster?

SARS-CoV-2, a recently emerged zoonotic virus, has resulted in unstoppable high morbidity and mortality rates worldwide. However, due to a limited knowledge of the dynamics of the SARS-CoV-2 infection, it has been observed that the current COVID-19 therapy has led to some clinical repercussions. We discuss the adverse effects of drugs for COVID-19 primarily based on some clinical trials. As therapeutic efficacy and toxicity of therapy may vary due to different, genetic determinants, sex, age and the ethnic background of test subjects, hence biomarker-based personalized therapy could be more appropriate. We will share our thoughts on the current landscape of personalized therapy as a roadmap to fight against SARS-CoV-2 or another emerging pathogen.

GPCRs as an emerging host-directed therapeutic target against mycobacterial infection: From notion to reality

Mycobacterium tuberculosis (M. tb) is one of the successful pathogens and claim millions of deaths across the globe. The emergence of drug resistance in M. tb has created new hurdles in the tuberculosis elimination programme worldwide. Hence, there is an unmet medical need for alternative therapy, which could be achieved by targeting the host's critical signalling pathways that are compromised during M. tb infection. In this review, we have summarized some of the findings involving the modulation of host GPCRs in the regulation of the mycobacterial infection. Understanding the role of these GPCRs not only unravels signalling pathways during infection but also provides clues for targeting critical signalling intermediates for the development of GPCR-based host-directive therapy.

Battling COVID-19 Pandemic: Sphingosine-1-Phosphate Analogs as an Adjunctive Therapy?

With the sudden outbreak of COVID-19 patient worldwide and associated mortality, it is critical to come up with an effective treatment against SARS-CoV-2. Studies suggest that mortality due to COVID 19 is mainly attributed to the hyper inflammatory response leading to cytokine storm and ARDS in infected patients. Sphingosine-1-phosphate receptor 1 (S1PR1) analogs, AAL-R and RP-002, have earlier provided in-vivo protection from the pathophysiological response during H1N1 influenza infection and improved mortality. Recently, it was shown that the treatment with sphingosine-1-phosphate receptor 1 analog, CYM5442, resulted in the significant dampening of the immune response upon H1N1 challenge in mice and improved survival of H1N1 infected mice in combination with an antiviral drug, oseltamivir. Hence, here we suggest to investigate the possible utility of using S1P analogs to treat COVID-19.

Sphingosine-1-phosphate signaling in Leishmania donovani infection in macrophages

BACKGROUND

Sphingosine-1-phosphate (S1P) is a crucial regulator of a wide array of cellular processes, such as apoptosis, cell proliferation, migration, and differentiation, but its role in Leishmania donovani infection is unknown.

METHODOLOGY/ PRINCIPAL FINDINGS

In the present study, we observed that L. donovani infection in THP-1 derived macrophages (TDM) leads to decrease in the expression of S1pr2 and S1pr3 at mRNA level. We further observed that Leishmania infection inhibits the phosphorylation of sphingosine kinase 1 (sphK1) in a time-dependent manner. Exogenous S1P supplementation decreases L. donovani induced ERK1/2 phosphorylation and increases p38 phosphorylation in TDM, resulting in a decrease in the intracellular parasite burden in a dose-dependent manner. On the other hand, sphK inhibition by DMS increases ERK1/2 phosphorylation leading to increased IL-10 and parasite load. To gain further insight, cytokines expression were checked in S1P supplemented TDM and we observed increase in IL-12, while decrease IL-10 expression at mRNA and protein levels. In addition, treatment of antagonist of S1PR2 and S1PR3 such as JTE-013 and CAY10444 respectively enhanced Leishmania-induced ERK1/2 phosphorylation and parasite load.

CONCLUSIONS

Our overall study not only reports the significant role of S1P signaling during L. donovani infection but also provides a novel platform for the development of new drugs against Leishmaniasis.

Investigation of molecular mechanism of recognition between citral and MARK4: A newer therapeutic approach to attenuate cancer cell progression

Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.

Elucidation of Dietary Polyphenolics as Potential Inhibitor of Microtubule Affinity Regulating Kinase 4: In silico and In vitro Studies

Microtubule affinity regulating kinase 4 (MARK4) is a Ser/Thr kinase belonging to AMPK-like family, has recently become an important drug target against cancer and neurodegenerative disorders. In this study, we have evaluated different natural dietary polyphenolics including rutin, quercetin, ferulic acid, hesperidin, gallic acid and vanillin as MARK4 inhibitors. All compounds are primarily binds to the active site cavity of MARK4. In silico observations were further complemented by the fluorescence-binding studies and isothermal titration calorimetry (ITC) measurements. We found that rutin and vanillin bind to MARK4 with a reasonably high affinity. ATPase and tau-phosphorylation assay further suggesting that rutin and vanillin inhibit the enzyme activity of MARK4 to a great extent. Cell proliferation, ROS quantification and Annexin-V staining studies are clearly providing sufficient evidences for the apoptotic potential of rutin and vanillin. In conclusion, rutin and vanillin may be considered as potential inhibitors for MARK4 and further exploited to design novel therapeutic molecules against MARK4 associated diseases.

Evaluation of human microtubule affinity-regulating kinase 4 inhibitors: fluorescence binding studies, enzyme, and cell assays

Human microtubule affinity-regulating kinase 4 (MARK4) is considered as an encouraging drug target for the design and development of inhibitors to cure several life-threatening diseases such as Alzheimer disease, cancer, obesity, and type-II diabetes. Recently, we have reported four ligands namely, BX-912, BX-795, PKR-inhibitor, and OTSSP167 (hydrochloride) which bind preferentially to the two different constructs of human MARK4 containing kinase domain. To ensure the role of ubiquitin-associated (UBA) domain in the ligand binding, we made a newer construct of MARK4 which contains both kinase and UBA domains, named as MARK4-F3. We observed that OTSSP167 (hydrochloride) binds to the MARK4-F3 with a binding constant (K) of 3.16 × 10⁶, M^-1 (±.21). However, UBA-domain of MARK4-F3 doesn't show any interaction with ligands directly as predicted by the molecular docking. To validate further, ATPase inhibition assays of all three constructs of MARK4 in the presence of mentioned ligands were carried out. An appreciable correlation between the binding experiments and ATPase inhibition assays of MARK4 was observed. In addition, cell-proliferation inhibition activity for all four ligands on the Human embryonic kidney (HEK-293) and breast cancer cell lines (MCF-7) was performed using MTT assay. IC₅₀ values of OTSSP167 for HEK-293 and MCF-7 were found to be 58.88 (±1.5), and 48.2 (±1.6), respectively. OTSSP167 among all four inhibitors, showed very good enzyme inhibition activity against three constructs of MARK4. Moreover, all four inhibitors showed anti-neuroblastoma activity and anticancer properties. In conclusion, OTSSP167 may be considered as a promising scaffold to discover novel inhibitors of MARK4.

Designing New Kinase Inhibitor Derivatives as Therapeutics Against Common Complex Diseases: Structural Basis of Microtubule Affinity-Regulating Kinase 4 (MARK4) Inhibition

Drug development for common complex diseases is in need of new molecular entities and actionable drug targets. MAP/microtubule affinity-regulating kinase 4 (MARK4) is associated with numerous diseases such as neurodegenerative disorders, obesity, cancer, and type 2 diabetes. Understanding the structural basis of ligands' (inhibitors) and substrates' binding to MARK4 is crucial to design new kinase inhibitors for therapeutic purposes. This study reports new observations on docking three well-known kinase inhibitors in the kinase domain of MARK4 variants and the calculated binding affinity. These variants of MARK4 are named as MARK4-F1 (59 N-terminal residues along with kinase domain) and MARK4-F2 (kinase domain of MARK4). We additionally performed molecular dynamics (MD) simulation and fluorescence binding studies to calculate the actual binding affinity of kinase inhibitors, BX-912, BX-795, and OTSSP167 (hydrochloride) for the MARK4. Docking analyses revealed that ligands bind in the large hydrophobic cavity of the kinase domain of MARK4 through several hydrophobic and hydrogen-bonded interactions. Simulations suggested that OTSSP167 (hydrochloride) is forming a stable complex, and hence the best inhibitor of MARK4. Intrinsic fluorescence of MARK4 was significantly quenched by addition of ligands, indicating their potential binding to MARK4. A lower KD value of MARK4 with OTSSP167 (hydrochloride) suggested that it is a better interacting partner than BX-912 and BX-795. These data form a basis for designing novel and potent OTSSP167 (hydrochloride) derivatives as therapeutic candidates against common complex diseases. The inhibitors designed as such might possibly suppress the growth of tumor-forming cells and be potentially applied for treatment of a wide range of human cancers as well.

Atypical PKC phosphorylates microtubule affinity-regulating kinase 4 in vitro

MAP/Microtubule affinity-regulating kinase 4 (MARK4), a Ser/Thr protein kinases, is related to the Par-1 (partitioning-defective) gene products, and is the human ortholog of Par-1. MARK4 shows its role in the cell polarity at the time of embryonic development. It is mostly located at the basal region of cells, providing apico-basal polarity. Here, we made two variants of human Par-1d (MARK4), kinase domain (MARK4-F2), and kinase domain along with 59 N-terminal residues (MARK4-F1) and saw their ATPase hydrolysis in the presence of each other. We observed that the activity of one variant was increased in the presence of other. We also demonstrated that both variants were phosphorylated by atypical PKC and their activities were increased in the presence of increasing concentration of atypical protein kinase c (aPKC). The phosphorylation was observed at the serine and threonine residues of MARK4. The interaction of MARK2 and MARK3 with aPKC and their negative regulation by aPKC is already known. This study confirms a functional link between aPKC and MARK4, two central determinants of cell polarity, and it suggests that aPKC may regulate all four members of Par-1 through phosphorylating them in polarized cells.

Human microtubule affinity-regulating kinase 4 is stable at extremes of pH

MAP/microtubule affinity-regulating kinase 4 (MARK4) is a member of adenosine monophosphate-activated protein kinases, directly associated with cancer and neurodegenerative diseases. Here, we have cloned, expressed, and purified two variants of MARK4 [the kinase domain (MARK4-F2), and kinase domain along with 59 N-terminal residues (MARK4-F1)] and compared their stability at varying pH range. Structural and functional changes were observed by incubating both forms of MARK4 in buffers of different pH. We measured the secondary structure of MARK4 using circular dichroism and tertiary structure by measuring intrinsic fluorescence and absorbance properties along with the size of proteins by dynamic light scattering. We observed that at extremes of pH (below pH 3.5 and above pH 9.0), MARK4 is quite stable. However, a remarkable aggregate formation was observed at intermediate pH (between pH 3.5 and 9.0). To further validate this result, we have modeled both forms of MARK4 and performed molecular dynamics simulation for 15 ns. The spectroscopic observations are in excellent agreement with the findings of molecular dynamics simulation. We also performed ATPase activity at varying pH and found a significant correlation of structure of MARK4 with its enzyme activity. It is interesting to note that both forms of MARK4 are showing a similar pattern of structure changes with reference to pH.

Lipid profile of women using oral contraceptive pills

Oral contraceptives (OCs) are the most popular type of birth control pills. The study was designed to examine the biochemical changes which occur due to the use of oral contraceptive pills (OCs). The study was based on the questionnaire for having the information of any reproductive history fasting, age, health, nature of menstrual cycle, bleeding, disease etc and blood profiling for biochemical analysis of the women includes high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), total cholesterol (TC) and triglycerides (TG). Lipid profiling was carried out by using a commercially available diagnostic test kits. SPSS was used to analyze the data. The results showed statistically significant differences among users of OCs compared to non-users. Total cholesterol (242.92 +/- 2.842 mg dL(-1)), HDL-C (58.65 +/- 1.098 mg dL(-1)), LDL-C (115.84 +/- 1.266 mg dL(-1)) and triglycerides (105.56 +/- 2.341 mg dL(-1)) were significantly higher compared to the non-users (Total cholesterol 218.49 +/- 1.762, HDL-C 48.17 +/- 0.543, LDL-C 100.321 +/- 0.951 and triglycerides 83.77 +/- 2.299 mg dL(-1)). The result suggests that OCs increase the level of high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), total cholesterol (TC) and triglycerides (TG).

Trend of complementary therapies in paediatric age group

OBJECTIVE

To assess the knowledge of mothers regarding commonly used Complimentary alternative medicines, their usage and various therapeutic choices for common ailments.

METHODS

A cross-sectional Survey on a predesigned proforma was done from July 2007- August 2007 in the out patient department of a tertiary care hospital. Consent was taken from the participants and 375 complete proformas were included in the study out of 500 interviewed.

RESULTS

Of the 375 mothers who were interviewed, 237 (63.2%) believed in alternative medicine whereas 138 (36.8%) did not believe in it. Complimentary alternative medicines (CAM) was used most often in children with respiratory tract and gastro intestinal symptoms, the most frequently used therapy was Honey 58.9% and Joshanda 31.2%, followed by Heeng 11.3% and brandy being used in 2.8% for respiratory complaints. Gastrointestinal symptoms were treated with Saunf water 28.4%, mint 20.6% and ajwain 17.7%. Higher education level was associated with more complementary medicine use. Majority of mothers used it for gastrointestinal problems and respiratory problems 24% and 22.2% respectively.

CONCLUSIONS

Mothers are aware of various available CAM and are using them for different ailments like honey for respiratory illnesses, Saunf and Ajwain for gastrointestinal problems as they have been found to have linctus and antispasmodic effects respectively. It has also been observed that the CAM was used in combination with other therapeutic modalities and not alone.

Present status of Maconellicoccus hirsutus (Hemiptera: Pseudococcidae) in the Mariana Islands and its control by two fortuitously introduced natural enemies

The mealybug Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae), attacks ornamental and fruit crops in the Mariana Islands. Insecticides cannot penetrate the heavy layers of wax that protect the insect's body. We surveyed the mealybug's locally recruited natural enemies and their effects on its population on Guam, Rota, Saipan, and Tinian to assess the need for introduction of exotic natural enemies. We monitored population densities of M. hirsutus, those of its natural enemies, and parasitism rates for 3 yr, 2005-2007. Our surveys revealed the presence of two parasitoids, Anagyrus kamali Moursi (Hymenoptera: Encyrtidae) and Allotropa sp. near mecrida (Walker) (Hymenoptera: Platygastridae), fortuitously introduced to the Mariana Islands with M. hirsutus. The predator Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) also was often found feeding on M. hirsutus. Population density of M. hirsutus was below the economic threshold at all locations. Rainfall seemed to affect mean numbers of M. hirsutus and mean numbers of eggs at some locations. On all four islands, the two parasitoids, complemented by the predator, were effectively controlling the M. hirsutus population. No evidence of hyperparasitism was recorded. Currently, economic damage by M. hirsutus is not a concern in the Mariana Islands, and additional parasitoids need not be introduced to control M. hirsutus.