Melatonin Action in Type 2 Diabetic Parotid Gland and Dental Pulp: In Vitro and Bioinformatic Findings

Type 2 diabetes mellitus (T2DM) is associated with functional deterioration of the salivary gland and dental pulp, related to oxidative stress. The aim was to integrate experimental and bioinformatic findings to analyze the cellular mechanism of melatonin (MEL) action in the human parotid gland and dental pulp in diabetes. Human parotid gland tissue was obtained from 16 non-diabetic and 16 diabetic participants, as well as human dental pulp from 15 non-diabetic and 15 diabetic participants. In human non-diabetic and diabetic parotid gland cells (hPGCs) as well as in dental pulp cells (hDPCs), cultured in hyper- and normoglycemic conditions, glial cell line-derived neurotrophic factor (GDNF), MEL, inducible nitric oxide synthase (iNOS) protein expression, and superoxide dismutase (SOD) activity were measured by enzyme-linked immunosorbent assay (ELISA) and spectrophotometrically. Bioinformatic analysis was performed using ShinyGO (v.0.75) application. Diabetic participants had increased GDNF and decreased MEL in parotid (p < 0.01) and dental pulp (p < 0.05) tissues, associated with increased iNOS and SOD activity. Normoglycemic hDPCs and non-diabetic hPGCs treated with 0.1 mM MEL had increased GDNF (p < 0.05), while hyperglycemic hDPCs treated with 1 mM MEL showed a decrease in up-regulated GDNF (p < 0.05). Enrichment analyses showed interference with stress and ATF/CREB signaling. MEL induced the stress-protective mechanism in hyperglycemic hDPCs and diabetic hPGCs, suggesting MEL could be beneficial for diabetes-associated disturbances in oral tissues.

VHL tumor suppressor as a novel potential candidate biomarker in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most common type of endocrine cancer, with an increasing incidence worldwide. The treatment of PTC is currently the subject of clinical controversy, making it critically important to identify molecular markers that would help improve the risk stratification of PTC patients and optimize the therapeutic approach. The VHL tumor suppressor gene has been implicated in tumorigenesis of various types of carcinoma and linked with their aggressive biological behavior. The role of VHL in the origin and development of PTC has only recently begun to be revealed. In this narrative review we attempt to summarize the existing knowledge that implicates VHL in PTC pathogenesis and to outline its potential significance as a candidate molecular biomarker for the grouping of PTC patients into high and low risk groups.

Dual function miR-205 is positively associated with ER and negatively with five-year survival in breast cancer patients

BACKGROUND

Precise molecular characterization of breast cancer, especially triple negative (TNBC) as the most lethal subtype, is needed to stratify patients for the individual treatment approach. MicroRNA-205 (miR-205) has tumor-suppressive and oncogenic functions across different cancers. Therefore, miR-205 might have a different role in TNBC and estrogen receptor (ER) positive BC. Our aim was to investigate how miR-205 expression is associated with ER/progesteron receptor status, clinical parameters, pathohistological characteristics of BC, and survival of patients METHODS: We determined miR-205 relative expressions in 73 primary breast tumors (50 TNBC and 23 ER+) by quantitative Real-time polymerase chain reaction (qPCR) and compared it to clinicopathological characteristics and outcome.

RESULTS

The highest levels of miR-205 were in the ER+ /PR+ group, and the lowest in the TNBC group (p = 0.009). Significantly higher levels of miR-205 were also observed in the ER+ compared with the ER-negative group, regardless of the PR status (p = 0.002). Low miR-205 expression level was associated with prognostic stage III in TNBC samples (p = 0.049). Patients who received adjuvant chemotherapy had significantly lower levels of miR-205 (p = 0.016). Patients who received hormone therapy had significantly higher levels of miR-205 (p = 0.007). The low-miR-205 patients had significantly higher 5-year survival rates (p = 0.041).

CONCLUSION

The expression of miR-205 in BC is subtype-specific and high expression is associated with the ER+ tumors. The miR-205 expression might be a useful marker of TNBC progression. High miR-205 expression had a detrimental effect on BC patient outcome. Our results indicate that miR-205 might be utilized in clinical practice as a biomarker and an adjunct parameter for the selection of the most effective therapeutic modality.

Effects of α5 GABAA receptor modulation on social interaction, memory, and neuroinflammation in a mouse model of Alzheimer's disease

Aims

GABAergic modulation involved in cognitive processing appears to be substantially changed in Alzheimer's disease (AD). In a widely used 5xFAD model of AD, we aimed to assess if negative and positive allosteric modulators of α5 GABA_A receptors (NAM and PAM, respectively) would affect social interaction, social, object and spatial memory, and neuroinflammation.

Methods

After 10‐day treatment with PAM, NAM, or solvent, 6‐month‐old transgenic and non‐transgenic 5xFAD mice underwent testing in a behavioral battery. Gene expressions of IL‐1β, IL‐6, TNF‐α, GFAP, and IBA‐1 were determined in hippocampus and prefrontal cortex by qPCR.

Results

PAM treatment impaired spatial learning in transgenic females compared to solvent‐treated transgenic females, and social recognition in transgenic and non‐transgenic males. NAM treatment declined social interaction in transgenic and non‐transgenic males, while had beneficial effect on cognitive flexibility in non‐transgenic males compared to solvent‐treated non‐transgenic males. Transgenic animals have not fully displayed cognitive symptoms, but neuroinflammation was confirmed. NAM reduced proinflammatory gene expressions in transgenic females and astrogliosis in transgenic males compared to pathological controls.

Conclusion

PAM and NAM failed to exert favorable behavioral effects in transgenic animals. Suppression of neuroinflammation obtained with NAM calls for more studies with GABAergic ligands in amyloid beta‐ and/or tau‐dependent models with prominent neuroinflammation.

Positive and Negative Selective Allosteric Modulators of α5 GABAA Receptors: Effects on Emotionality, Motivation, and Motor Function in the 5xFAD Model of Alzheimer's Disease

BACKGROUND

Positive and negative allosteric modulators of α5 GABAA receptors (PAM and NAM, respectively) are worthy of investigation as putative treatments of Alzheimer's disease (AD). However, their potential to modify a dynamic range of behaviors in AD models needs to be systematically examined.

OBJECTIVE

The study aimed to assess effects of MP-III-022 as PAM and PWZ-029 as NAM on emotional reactivity, motivation, and motor function, as well as on gene expression of GABRA2, GABRA3 and GABRA5 subunit of GABAA receptors in prefrontal cortex (PFC) and hippocampus (HC) in 5xFAD mice, as an early-onset transgenic AD model.

METHODS

The 6-month-old 5xFAD transgenic and non-transgenic mice of both genders underwent a battery of reflexes and behavioral tests (sensorimotor tests, elevated plus maze, and open field) after 10-day intraperitoneal treatment with MP-III-022, PWZ-029, or solvent. The behavioral battery was followed by qPCR analysis of gene expression.

RESULTS

MP-III-022 induced a decline in motor function, while PWZ-029 further decreased emotionality of transgenic males, as compared to the transgenic control. No interfering effects on non-cognitive behavior were observed in female mice. In HC, both treatments reversed reciprocal GABRA2 and GABRA3 changes in transgenic females. In PFC, MP-III-022 decreased GABRA5 in both genders, while PWZ-029 increased GABRA2 in male transgenic animals.

CONCLUSION

Gender-dependent protracted effects of PAMs and NAMs in AD model, with detrimental impact on motor capabilities of PAM, and attenuation of emotionality elicited by NAM in transgenic males, were revealed. This favors future research of α5 GABAA receptor modulation in females as more promising.

Vasodilatory effects of a variety of positive allosteric modulators of GABAA receptors on rat thoracic aorta

Different subtypes of GABAA (gamma-aminobutyric acid A) receptors, through their specific regional and cellular localization, are involved in the manifestation of various functions, both at the central and peripheral levels. We hypothesized that various non-neuronal GABAA receptors are expressed on blood vessels, through which positive allosteric modulators of GABAA receptors exhibit vasodilatory effects. This study involved two parts: one to determine the presence of α1-6 subunit GABAA receptor mRNAs in the rat thoracic aorta, and the other to determine the vasoactivity of the various selective and non-selective positive GABAA receptor modulators: zolpidem (α1-selective), XHe-III-074 (α4-selective), MP-III-022 (α5-selective), DK-I-56-1 (α6-selective), SH-I-048A and diazepam (non-selective). Reverse transcription-polymerase chain reaction (RT-PCR) analysis data demonstrated for the first time the expression of α1, α2, α3, α4 and α5 subunits in the rat thoracic aorta tissue. Tissue bath assays on isolated rat aortic rings revealed significant vasodilatory effects of diazepam, SH-I-048A, XHe-III-074, MP-III-022 and DK-I-56-1, all in terms of achieved relaxations (over 50% of relative tension decrease), as well as in terms of preventive effects on phenylephrine (PE) contraction. Diazepam was the most efficient ligand in the present study, while zolpidem showed the weakest vascular effects. In addition, diazepam-induced relaxations in the presence of antagonists PK11195 or bicuculline were significantly reduced (P < 0.001 and P < 0.05, respectively) at lower concentrations of diazepam (10-7 M and 3 × 10-7 M). The present work suggests that the observed vasoactivity is due to modulation of "vascular" GABAA receptors, which after further detailed research may provide a therapeutic target.

Estrogen Receptor Beta: The Promising Biomarker and Potential Target in Metastases

The discovery of the Estrogen Receptor Beta (ERβ) in 1996 opened new perspectives in the diagnostics and therapy of different types of cancer. Here, we present a review of the present research knowledge about its role in endocrine-related cancers: breast, prostate, and thyroid, and colorectal cancers. We also discuss the reasons for the controversy of its role in carcinogenesis and why it is still not in use as a biomarker in clinical practice. Given that the diagnostics and therapy would benefit from the introduction of new biomarkers, we suggest ways to overcome the contradictions in elucidating the role of ERβ.

Higher miR-21 expression in invasive breast carcinomas is associated with positive estrogen and progesterone receptor status in patients from Serbia

MicroRNAs play essential role in breast carcinoma progression and invasion. Our principal goals were to assess clinicopathological and prognostic correlations of microRNA-21 (miR-21) expression levels in a group of 39 Serbian breast cancer patients with invasive lobular (ILC), ductal (IDC), or mixed (ILC-IDC) breast carcinomas and in order to discover the role of miR-21 in potential novel form of stratification of the patients with different estrogen receptor (ER) and progesterone receptor (PR) status. MiR-21 expression levels were measured by stem-loop real-time RT-PCR using TaqMan technology. ER, PR, human epidermal growth factor 2 receptor (Her-2), and proliferative index (Ki-67) were evaluated by immunohistochemistry. MiR-21 levels do not vary among ILC, IDC, and ILC-IDC subgroups. MiR-21 expression levels varied significantly in the age, tumor size, Ki-67, and different grade (p = 0.030, p = 0.036, p = 0.027 and p = 0.032, respectively) subgroups. ER+ and PR+ showed higher miR-21 levels than their negative receptor status paired groups ER- and PR- with p = 0.012 and p = 0.018, respectively. MiR-21 positively correlated with ER and PR status (p = 0.018, ρ = 0.379 and p = 0.034, ρ = 0.345, respectively). Our findings suggest that miR-21 emulates transitional form of expression and that the levels of expression might be useful for stratification of the patients with different receptor status with the purpose to seek for new therapy approaches especially for the patients with the lack of response to conventional endocrine therapy.

The difference in miR-21 expression levels between invasive and non-invasive breast cancers emphasizes its role in breast cancer invasion

MicroRNA-21 (miR-21) overexpression is characteristic for various types of tumors, but it is still unknown whether its expression levels differ between invasive and non-invasive breast carcinomas. The main goal of the study was to determine the difference in miR-21 expression among normal tissue, non-invasive, invasive with non-invasive component, and pure invasive breast cancer samples, to explain its potential role and significance in breast cancer invasiveness. The second goal was to propose miR-21 as molecular marker of breast cancer invasiveness and potential target for future anti-miR therapies for the prevention of invasion and metastasis. In order to reveal the role of miR-21 in breast cancer invasiveness, we measured miR-21 expression levels in 44 breast cancer and four normal samples by stem-loop real-time RT-PCR using TaqMan technology. Relative expression levels of miR-21 were significantly higher in invasive than in other groups (P=0.002) and significantly higher in invasive compared with invasive with non-invasive component group in histological (P=0.043) and nuclear grade 2 (P=0.036), estrogen-receptor-positive (ER+) (P=0.006), progesterone-receptor-positive (PR+) (P=0.008), ER+PR+ (P=0.007), and proliferation index (Ki-67)≤20% (P=0.036) tumors. Our findings suggest that miR-21 could be independent molecular marker of breast cancer invasiveness and potential target for future anti-miR therapies for the prevention of invasion and metastasis.

Blocks of the foramen rotundum and the oval foramen: a reappraisal of extraoral maxillary and mandibular nerve injections

OBJECTIVE

To present our experience of regional anaesthesia with blocks of the foramen rotundum and the oval foramen.

DESIGN

Open study.

SETTING

University Hospital, Beograd, Yugoslavia.

SUBJECTS

107 patients who underwent 58 maxillary and 49 mandibular nerve blocks.

INTERVENTIONS

Injection of 2% lignocaine with adrenaline 1/80,000 with an 18 G venflon or 20 G spinal needle.

MAIN OUTCOME MEASURES

Quality of anaesthesia and morbidity.

RESULTS

49 of the 58 maxillary (84%) and 45 of the 49 mandibular (92%) nerve blocks were successful (no sensitivity to pinprick in the distribution of the injected nerve and a painless operation). There were 17 complications (26%), 8 in the maxillary and 9 in the mandibular group. All complications were minor and transient, and 6 could be attributed to anhydrous glycerol rather than the injection technique itself.

CONCLUSION

Blocks of the foramen rotundum and the oval foramen achieve good regional anaesthesia in the maxillofacial region.

Peripheral streptomycin/lidocaine injections versus lidocaine alone in the treatment of idiopathic trigeminal neuralgia. A double blind controlled trial

Seventeen patients with long-lasting idiopathic trigeminal neuralgia (ITN) were treated with either five, weekly peripheral streptomycin/lidocaine (S/L) or lidocaine alone injections, in a double blind controlled study. Eight patients responded initially to the treatment in the S/L group and three patients in the lidocaine group. Pain recurred in four patients from the S/L group within two weeks and six months following the last injection. One patient from the lidocaine group remained pain-free for eight months. At the final assessment, three patients from the S/L group and two patients from the lidocaine group remained pain-free up to 30 months. Neither treatment affected sensory functions of the injected nerves. It is concluded that S/L injections are initially effective in the treatment of ITN. In the long term, however, their effects are similar to the effects of lidocaine alone.

[Apicoectomy performed after supervoltage radiotherapy in the region of oral cavity and neck: case report]

The author describes a case of apicoectomy of the lower canine in a patient who was previously exposed to supervoltage radiotherapy in the oral cavity and neck regions. After the comment on the uneventful postoperative course and the absence of complications one year and a half later, the author points out that apicoectomy should be taken into account when dental care of irradiated patients was planned.

[Possible usage of parallax phenomenon in dental radiography]

The authors describe a method of X-ray recording which uses the phenomenon of parallax in determination of exact localisation and inter-relationship of some elements within the upper and lower jaws. By describing the method in detail, the authors also point out its advantages in everyday estimation of the position of impacted teeth and their relationship to the surrounding anatomical points.

Mandibular versus inferior dental anaesthesia: clinical assessment of 3 different techniques

Inferior dental anaesthesia via the direct intraoral approach, mandibular conduction anaesthesia via extraoral landmarks (Gow-Gates) and mandibular conduction anaesthesia via the tuberosity approach (Akinosi) were evaluated using onset and duration of anaesthesia, pain during injection, aspiration test, pinprick, depth and frequency of anaesthesia. 90 patients undergoing simple tooth extraction were randomly selected into 3 groups. They were given injections of 2 ml of 2% lidocaine with adrenaline (1:80,000). All techniques were mostly painless, none of them showing any special advantage in that sense. The differences in duration of anaesthesia among the applied techniques were insignificant. Positive aspirations were most frequently observed with the direct method of inferior dental anaesthesia, but this method gave the best result for the frequency of anaesthesia. After using the Gow-Gates method, the external branches of the buccal nerve were usually anaesthetized but the onset of anaesthesia was relatively slow. Mandibular conduction anaesthesia via the tuberosity approach did not show any particular advantage over the other 2 techniques in this investigation. A progress study is needed to determine more precisely the aspiration rate and frequency of anaesthesia for all the techniques.

Peripheral streptomycin/lidocaine injections in the treatment of idiopathic trigeminal neuralgia. A preliminary report

Streptomycin sulphate dissolved in 2% lidocaine solution was deposited adjacent to peripheral branches of maxillary or mandibular nerves in 20 patients with idiopathic trigeminal neuralgia. The patients were given five injections at approximately one week intervals. In the postinjection period, once the local anaesthetic had worn off, apparently normal sensation returned. All patients obtained pain relief, only four having a recurrence of symptoms. The remaining 16 patients remained free of pain after periods of up to 30 months.

Abscopal effects of local fractionated X-irradiation of face and jaw region

The abscopal effects of high doses of X-irradiation, 6000 R given in 12 fractions locally on rat face and jaw region, upon the haematopoietic and lymphatic tissues, were studied. Haematological and pathophysiological studies were performed. Peripheral blood samples were taken after the 7th, 17th and 27th day during the course of the irradiation. 24 hours after the last irradiation the smears of femur bone-marrow were done. In the smears, the cells of erythrocyte and leukocyte series, as well as their mitotic index were determined. 24 hours after the irradiation the pieces of lymph nodes and salivary glands were taken for histological analysis. A significant depression of peripheral leukocyte counts was found in all observation intervals as well as the change in mitotic index of granulocyte series in bone marrow. No significant histological changes on the lymph nodes and salivary gland section were found 24 hours after the last irradiation.