Beta cell specific cannabinoid 1 receptor deletion counteracts progression to hyperglycemia in non-obese diabetic mice.

OBJECTIVE: Type 1 diabetes (T1D) occurs because of islet infiltration by autoreactive immune cells leading to destruction of beta cells and it is becoming evident that beta cell dysfunction partakes in this process. We previously reported that genetic deletion and pharmacological antagonism of the cannabinoid 1 receptor (CB1) in mice improves insulin synthesis and secretion, upregulates glucose sensing machinery, favors beta cell survival by reducing apoptosis, and enhances beta cell proliferation. Moreover, beta cell specific deletion of CB1 protected mice fed a high fat high sugar diet against islet inflammation and beta cell dysfunction. Therefore, we hypothesized that it would mitigate the dysfunction of beta cells in the precipitating events leading to T1D. METHODS: We genetically deleted CB1 specifically from beta cells in non-obese diabetic (NOD; NOD RIP Cre+ Cnr1fl/fl) mice. We evaluated female NOD RIP Cre+ Cnr1fl/fl mice and their NOD RIP Cre-Cnr1fl/fl and NOD RIP Cre+ Cnr1Wt/Wt littermates for onset of hyperglycemia over 26 weeks. We also examined islet morphology, islet infiltration by immune cells and beta cell function and proliferation. RESULTS: Beta cell specific deletion of CB1 in NOD mice significantly reduced the incidence of hyperglycemia by preserving beta cell function and mass. Deletion also prevented beta cell apoptosis and aggressive insulitis in NOD RIP Cre+ Cnr1fl/fl mice compared to wild-type littermates. NOD RIP Cre+ Cnr1fl/fl islets maintained normal morphology with no evidence of beta cell dedifferentiation or appearance of extra islet beta cells, indicating that protection from autoimmunity is inherent to genetic deletion of beta cell CB1. Pancreatic lymph node Treg cells were significantly higher in NOD RIP Cre+ Cnr1fl/flvs NOD RIP Cre-Cnr1fl/fl. CONCLUSIONS: Collectively these data demonstrate how protection of beta cells from metabolic stress during the active phase of T1D can ameliorate destructive insulitis and provides evidence for CB1 as a potential pharmacologic target in T1D.

Pancreatic ß cell derived extracellular vesicles containing surface preproinsulin are involved in glucose stimulated insulin secretion.

AIMS: Extracellular vesicles (EVs) are involved in intercellular communication and are a topic of increasing interest due to their therapeutic potential. The aim of this study was to determine whether human islet-derived EVs contain insulin, and if so, what role do they play in glucose stimulated insulin secretion. MAIN METHODS: We isolated EVs from human islets culture and plasma to probe for insulin. Plasma from hyperglycemic glucose clamp experiments were also used to isolate and measure EV insulin content in response to a secretory stimulus. We performed immunogold electron microscopy for insulin presence in EVs. Co-culture experiments of isolated EVs with fresh islets were performed to examine the effect of EV cargo on insulin receptor signaling. KEY FINDINGS: EVs isolated from culture medium contained insulin. Glucose treatment of islets increased the level of EV insulin. Hyperglycemic glucose clamp experiments in humans also lead to increased levels of insulin in plasma-derived EVs. Immunogold electron microscopy and proteinase K-digestion experiments demonstrated that insulin in EVs predominantly associated with the exterior surface of EVs while western blot analyses uncovered the presence of only preproinsulin in EVs. Membrane-bound preproinsulin in EVs was capable of activating insulin signaling pathway in an insulin receptor-dependent manner. The physiological relevance of this finding was observed in priming of human naïve islets by EVs during glucose stimulated insulin secretion. SIGNIFICANCE: Our data suggest that (1) human islets secret insulin via an alternate pathway (EV-mediated) other than conventional granule-mediated insulin secretion, and (2) EV membrane bound preproinsulin is biologically active.

Long-Term Dysfunction of Taste Papillae in SARS-CoV-2.

BACKGROUND: We sought to determine whether ongoing taste disturbance in the postacute sequelae of coronavirus disease 2019 period is associated with persistent virus in primary taste tissue. METHODS: We performed fungiform papillae biopsies on 16 patients who reported taste disturbance lasting more than 6 weeks after molecularly determined severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Then, on multiple occasions, we rebiopsied 10 of those patients who still had taste complaints for at least 6 months postinfection. Fungiform papillae obtained from other patients before March 2020 served as negative controls. We performed hematoxylin and eosin staining to examine fungiform papillae morphology and immunofluorescence and fluorescence in situ hybridization to look for evidence of persistent viral infection and immune response. RESULTS: In all patients, we found evidence of SARS-CoV-2, accompanying immune response and misshapen or absent taste buds with loss of intergemmal neurite fibers. Six patients reported normal taste perception by 6 months postinfection and were not further biopsied. In the remaining 10, the virus was eliminated in a seemingly random fashion from their fungiform papillae, but four patients still, by history, reported incomplete return to preinfection taste perception by the time we wrote this report. CONCLUSIONS: Our data show a temporal association in patients between functional taste, taste papillae morphology, and the presence of SARS-CoV-2 and its associated immunological changes. (Funded by Intramural Research Program/National Institute on Aging/National Institute of Allergy and Infectious Diseases/National Institutes of Health; ClinicalTrials.gov numbers NCT03366168 and NCT04565067.).

Development and validation of a score predicting mortality for older patients with mitral regurgitation.

OBJECTIVE: To develop and validate a user-friendly risk score for older mitral regurgitation (MR) patients, referred to as the Elder-MR score. METHODS: The China Senile Valvular Heart Disease (China-DVD) Cohort Study functioned as the development cohort, while the China Valvular Heart Disease (China-VHD) Study was employed for external validation. We included patients aged 60 years and above receiving medical treatment for moderate or severe MR (2274 patients in the development cohort and 1929 patients in the validation cohort). Candidate predictors were chosen using Cox's proportional hazards model and stepwise selection with Akaike's information criterion. RESULTS: Eight predictors were identified: age ≥ 75 years, body mass index < 20 kg/m2, NYHA class III/IV, secondary MR, anemia, estimated glomerular filtration rate < 60 mL/min per 1.73 m2, albumin < 35 g/L, and left ventricular ejection fraction < 60%. The model displayed satisfactory performance in predicting one-year mortality in both the development cohort (C-statistic = 0.73, 95% CI: 0.69-0.77, Brier score = 0.06) and the validation cohort (C-statistic = 0.73, 95% CI: 0.68-0.78, Brier score = 0.06). The Elder-MR score ranges from 0 to 15 points. At a one-year follow-up, each point increase in the Elder-MR score represents a 1.27-fold risk of death (HR = 1.27, 95% CI: 1.21-1.34, P < 0.001) in the development cohort and a 1.24-fold risk of death (HR = 1.24, 95% CI: 1.17-1.30, P < 0.001) in the validation cohort. Compared to EuroSCORE II, the Elder-MR score demonstrated superior predictive accuracy for one-year mortality in the validation cohort (C-statistic = 0.71 vs. 0.70, net reclassification improvement = 0.320, P < 0.01; integrated discrimination improvement = 0.029, P < 0.01). CONCLUSIONS: The Elder-MR score may serve as an effective risk stratification tool to assist clinical decision-making in older MR patients.

AAV5-mediated manipulation of insulin expression in choroid plexus has long-term metabolic and behavioral consequences.

The choroid plexus (CP) is a source of trophic factors for the developing and mature brain. Insulin is produced in epithelial cells of the CP (EChPs), and its secretion is stimulated by Htr2c-mediated signaling. We modulated insulin expression in EChPs with intracerebroventricular injections of AAV5. Insulin overexpression in CP decelerates food intake, whereas its knockdown has the opposite effect. Insulin overexpression also results in reduced anxious behavior. Transcriptomic changes in the hypothalamus, especially in synapse-related processes, are also seen in mice overexpressing insulin in CP. Last, activation of Gq signaling in CP leads to acute Akt phosphorylation in neurons of the arcuate nucleus, indicating a direct action of CP-derived insulin on the hypothalamus. Taken together, our findings signify that CP is a relevant source of insulin in the central nervous system and that CP-derived insulin should be taken into consideration in future work pertaining to insulin actions in the brain.

Cannabinoid CB2 receptors modulate alcohol induced behavior, and neuro-immune dysregulation in mice.

The identification of additional lipid mediators, enzymes, and receptors revealed an expanded endocannabinoid system (ECS) called the endocannabinoidome (eCBome). Furthermore, eCBome research using wild type and genetically modified mice indicate the involvement of this system in modulating alcohol induced neuroinflammatory alterations associated with behavioral impairments and the release of proinflammatory cytokines. We investigated the role of cannabinoid type 2 receptors (CB2Rs) in modulating behavioral and neuro-immune changes induced by alcohol using conditional knockout (cKO) mice with selective deletion of CB2Rs in dopamine neurons (DAT-Cnr2) and in microglia (Cx3Cr1-Cnr2) cKO mice. We used a battery of behavioral tests including locomotor and wheel running activity, rotarod performance test, and alcohol preference tests to evaluate behavioral changes induced by alcohol. ELISA assay was used, to detect alterations in IL-6, IL-1α, and IL-1ß in the prefrontal cortex, striatum, and hippocampal regions of mice to investigate the role of CB2Rs in neuroinflammation induced by alcohol in the brain. The involvement of cannabinoid receptors in alcohol-induced behavior was also evaluated using the non-selective cannabinoid receptor mixed agonist WIN 55,212-2. The results showed that cell-type specific deletion of CB2Rs in dopamine neurons and microglia significantly and differentially altered locomotor activity and rotarod performance activities. The result also revealed that cell-type specific deletion of CB2Rs enhanced alcohol-induced inflammation, and WIN significantly reduced alcohol preference in all genotypes compared to the vehicle controls. These findings suggest that the involvement of CB2Rs in modulating behavioral and neuroinflammatory alterations induced by alcohol may be potential therapeutic targets in the treatment of alcohol use disorder.

Can Measuring the 'Dual Anchors of Aorta' Enhance the Success Rate of TAVR?-A Single-Center Experience.

INTRODUCTION: Chronic severe aortic regurgitation (AR) has a poor long-term prognosis, especially among old-age patients. Considering their advancing age, the surgical approach of aortic valve replacement may not always be the best alternative modality of treatment in such patients. Therefore, this study's primary goal was to provide an initial summary of the medium- and short-term clinical effectiveness of transcatheter aortic valve replacement (TAVR) guided by accurate multi-detector computed tomography (MDCT) measurements in patients with severe and chronic AR, especially in elderly patients. METHODS: The study enrolled retrospectively and prospectively patients diagnosed with severe AR who eventually underwent TAVR procedure from January 2019 to September 2022 at Fuwai cardiovascular Hospital, Beijing. Baseline information, MDCT measurements, anatomical classification, perioperative, and 1-year follow-up outcomes were collected and analyzed. Based on a novel anatomical categorization and dual anchoring theory, patients were divided into four categories according to the level of anchoring area. Type 1, 2, and 3 patients (with at least two anchoring regions) will receive TAVR with a transcatheter heart valve (THV), but Type 4 patients (with zero or one anchoring location) will be deemed unsuitable for TAVR and will instead receive medical care (retrospectively enrolled patients who already underwent TAVR are an exception). RESULTS: The mean age of the 37 patients with severe chronic AR was 73.1 ± 8.7 years, and 23 patients (62.2%) were male. The American Association of Thoracic Surgeons' score was 8.6 ± 2.1%. The MDCT anatomical classification included 17 cases of type 1 (45.9%), 3 cases of type 2 (8.1%), 13 cases of type 3 (35.1%), and 4 cases of Type 4 (10.8%). The VitaFlow valve (MicroPort, Shanghai, China) was implanted in 19 patients (51.3%), while the Venus A valve (Venus MedTech, Hangzhou, China) was implanted in 18 patients (48.6%). Immediate TAVR procedural and device success rates were 86.5% and 67.6%, respectively, while eight cases (21.6%) required THV-in-THV implantation, and nine cases (24.3%) required permanent pacemaker implantation. Univariate regression analysis revealed that the major factors affecting TAVR device failure were sinotubular junction diameter, THV type, and MDCT anatomical classification (p < 0.05). Compared with the baseline, the left ventricular ejection fraction gradually increased, while the left ventricular end-diastolic diameter remained small, and the N-terminal-pro hormone B-type natriuretic peptide level significantly decreased within one year. CONCLUSION: According to the results of our study, TAVR with a self-expanding THV is safe and feasible for patients with chronic severe AR, particularly for those who meet the criteria for the appropriate MDCT anatomical classification with intact dual aortic anchors, and it has a significant clinical effect for at least a year.

Novel Hominid-Specific IAPP Isoforms: Potential Biomarkers of Early Alzheimer's Disease and Inhibitors of Amyloid Formation.

(1) Background and aims: Amyloidosis due to aggregation of amyloid-ß (Aß42) is a key pathogenic event in Alzheimer's disease (AD), whereas aggregation of mature islet amyloid polypeptide (IAPP37) in human islets leads to ß-cell dysfunction. The aim of this study is to uncover potential biomarkers that might additionally point to therapy for early AD patients. (2) Methods: We used bioinformatic approach to uncover novel IAPP isoforms and developed a quantitative selective reaction monitoring (SRM) proteomic assay to measure their peptide levels in human plasma and CSF from individuals with early AD and controls, as well as postmortem cerebrum of clinical confirmed AD and controls. We used Thioflavin T amyloid reporter assay to measure the IAPP isoform fibrillation propensity and anti-amyloid potential against aggregation of Aß42 and IAPP37. (3) Results: We uncovered hominid-specific IAPP isoforms: hIAPPß, which encodes an elongated propeptide, and hIAPPγ, which is processed to mature IAPP25 instead of IAPP37. We found that hIAPPß was significantly reduced in the plasma of AD patients with the accuracy of 89%. We uncovered that IAPP25 and a GDNF derived DNSP11 were nonaggregating peptides that inhibited the aggregation of IAPP37 and Aß42. (4) Conclusions: The novel peptides derived from hIAPP isoforms have potential to serve as blood-derived biomarkers for early AD and be developed as peptide based anti-amyloid medicine.

Alcohol induced behavioral and immune perturbations are attenuated by activation of CB2 cannabinoid receptors.

The endocannabinoidome (eCBome) is the expanded endocannabinoid system (ECS) and studies show that there is a link between this system and how it modulates alcohol induced neuroinflammation. Using conditional knockout (cKO) mice with selective deletion of cannabinoid type 2 receptors (CB2Rs) in dopamine neurons (DAT-Cnr2) and in microglia (Cx3Cr1-Cnr2), we investigated how CB2Rs modulate behavioral and neuroinflammation induced by alcohol. Behavioral tests including locomotor and wheel running activity, rotarod performance test, and alcohol preference tests were used to evaluate behavioral changes induced by alcohol. Using ELISA assay, we investigated the level of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1α (IL-1α), and interleukin-1ß (IL-1ß) in the hippocampus of mice. The findings demonstrated that locomotor activity, wheel running, and rotarod performance activities were significantly affected by cell-type specific deletion of CB2Rs in dopamine neurons and microglia. The non-selective CB2R agonist, WIN 55,212-2, reduced alcohol preference in the wild type and cell-type specific CB2R cKO mice. In addition, the result showed that cell-type specific deletion of CB2Rs per se and administration of alcohol to CB2R cKO mice increased the expression of proinflammatory cytokines in the hippocampus. These findings suggest the involvement of CB2Rs in modulating behavioral and immune alterations induced by alcohol.

A novel anatomic classification to guide transcatheter aortic valve replacement for pure aortic regurgitation.

BACKGROUND: The success of transcatheter aortic valve replacement (TAVR) in native aortic regurgitation (AR) is limited by the absence of calcified anchoring structures. We sought to evaluate transfemoral TAVR in patients with native AR using a novel aortic root imaging classification. METHODS: From March to November 2021, 81 patients with severe AR were prospectively enrolled in 2 cardiac centers in China. All were evaluated using multidetector computed tomography (MDCT) and classified into 4 anatomic types in reference to transcatheter heart valve (THV) anchoring: Type 1: anchoring at the left ventricular outflow tract (LVOT), annulus, and ascending aorta (AA); Type 2: anchoring at the annulus and AA; Type 3: anchoring at the annulus and LVOT; and Type 4: anchoring at only 1 level or none at all. Based on the dual-anchoring strategy, patients with Types 1-3 were considered TAVR candidates. Procedural and 30-day outcomes were assessed according to Valve Academic Research Consortium-3 definitions. RESULTS: TAVR was performed in 32 (39.5%) patients (71.9 ± 8.0 years of age, 71.9% were male) using 2 self-expanding THVs. Types 1, 2, and 3 comprised 13 (40.6%), 11 (34.4%), and 8 (25.0%) cases, respectively. The procedural and device success rates were 100% and 93.8%, respectively, with 2 THV migration. Eight patients (25.0%) required a permanent pacemaker, and 2 (6.3%) developed moderate paravalvular leaks. No deaths or other major complications occurred during the study. CONCLUSIONS: The novel anatomic classification and dual-anchoring strategy were associated with a high procedural success rate with favorable short-term safety and clinical outcomes.

Repeated cocaine administration upregulates CB2 receptor expression in striatal medium-spiny neurons that express dopamine D1 receptors in mice.

Cannabinoid CB2 receptors (CB2R) are importantly involved in drug reward and addiction. However, the cellular mechanisms underlying CB2R action remain unclear. We have previously reported that cocaine self-administration upregulates CB2R expression in midbrain dopamine (DA) neurons. In the present study, we investigated whether cocaine or heroin also alters CB2R expression in striatal medium-spiny neurons that express dopamine D1 or D2 receptors (D1-MSNs, D2-MSNs) and microglia. Due to the concern of CB2R antibody specificity, we developed three mouse CB2-specific probes to detect CB2R mRNA using quantitative RT-PCR and RNAscope in situ hybridization (ISH) assays. We found that a single injection of cocaine failed to alter, while repeated cocaine injections or self-administration dose-dependently upregulated CB2R gene expression in both brain (cortex and striatum) and periphery (spleen). In contrast, repeated administration of heroin produced a dose-dependent reduction in striatal CB2 mRNA expression. RNAscope ISH assays detected CB2R mRNA in striatal D1- and D2-MSNs, not in microglia. We then used transgenic CX3CR1eGFP/+ microglia reporter mice and D1- or D2-Cre-RiboTag mice to purify striatal microglia or ribosome-associated mRNAs from CX3CR1eGFP/+, D1-MSNs, or D2-MSNs, respectively. We found that CB2R upregulation occurred mainly in D1-MSNs, not in D2-MSNs or microglia, in the nucleus accumbens rather than the dorsal striatum. These findings indicate that repeated cocaine exposure may upregulate CB2R expression in both brain and spleen, with regional and cell type-specific profiles. In the striatum, CB2R upregulation occurs mainly in D1-MSNs in the nucleus accumbens. Given the important role of D1-MSNs in brain reward function, the present findings provide new insight into mechanisms by which brain CB2Rs modulate cocaine action.

Novel Human Insulin Isoforms and Cα-Peptide Product in Islets of Langerhans and Choroid Plexus.

Human insulin (INS) gene diverged from the ancestral genes of invertebrate and mammalian species millions of years ago. We previously found that mouse insulin gene (Ins2) isoforms are expressed in brain choroid plexus (ChP) epithelium cells, where insulin secretion is regulated by serotonin and not by glucose. We further compared human INS isoform expression in postmortem ChP and islets of Langerhans. We uncovered novel INS upstream open reading frame isoforms and their protein products. In addition, we found a novel alternatively spliced isoform that translates to a 74-amino acid (AA) proinsulin containing a shorter 19-AA C-peptide sequence, herein designated Cα-peptide. The middle portion of the conventional C-peptide contains ß-sheet (GQVEL) and hairpin (GGGPG) motifs that are not present in Cα-peptide. Islet amyloid polypeptide (IAPP) is not expressed in ChP, and its amyloid formation was inhibited in vitro more efficiently by Cα-peptide than by C-peptide. Of clinical relevance, the ratio of the 74-AA proinsulin to proconvertase-processed Cα-peptide was significantly increased in islets from type 2 diabetes mellitus autopsy donors. Intriguingly, 100 years after the discovery of insulin, we found that INS isoforms are present in ChP from insulin-deficient autopsy donors.

Effects of Danhong Injection () on Peri-Procedural Myocardial Injury and Microcirculatory Resistance in Patients with Unstable Angina Undergoing Elective Percutaneous Coronary Intervention: A Pilot Randomized Study.

OBJECTIVE: To evaluate the effect of Danhong Injection (, DH) on the index of microcirculatory resistance (IMR) and myocardial injury in patients with unstable angina undergoing elective percutaneous coronary intervention (PCI). METHODS: Seventy-eight patients with unstable angina were randomly divided into DH group (39 cases) and the control group (39 cases) during elective PCI. Randomization was performed using a random-number table. The DH group received DH at a dosage of 40 mL (mixed with 250 mL saline, covered by a light-proof bag, intravenous drip) during PCI and daily for 7 consecutive days, while the control group only received the same dosage of saline. Both groups received standardized treatment. The IMR and fractional flow reserve (FFR) were measured at maximal hyperemia before and after PCI. Myocardial markers, including myoglobin, creatine kinase (CK), creatine kinase MB (CK-MB), and coronary troponin T (cTnT) values were measured at baseline and 24 h after PCI. RESULTS: Among the 78 patients enrolled, the baseline and procedural characteristics were similar between the two groups. There was no significant difference in pre-PCI myocardial markers and coronary physiological indexes between the two groups. However, post-PCI CK and CK-MB levels in the DH group were significantly lower than those in the control group (111.97 ± 80.97 vs. 165.47 ± 102.99, P=0.013; 13.08 ± 6.90 vs. 19.75 ± 15.49, P=0.016). Post-PCI myoglobin and cTNT-positive tend to be lower in the DH group than in the control group but did not reach statistical significance (88.07 ± 52.36 vs. 108.13 ± 90.94, P=0.52; 2.56% vs.7.69%, P=0.065). Compared with the control group, the post-IMR levels of the DH group tended to decrease, but there was no statistical difference (20.73 ± 13.15 vs. 26.37 ± 12.31, P=0.05). There were no statistical differences in post-FFR in both groups. The peri-procedural myocardial injury of the DH group was significantly lower than that of the control group (2.56% vs. 15.38%, P=0.025). During the 30-d follow-up period, no major adverse cardiovascular events occurred in either group. CONCLUSION: This study demonstrated benefit of DH in reducing myocardial injury and potential preserving microvascular function in patients with unstable angina undergoing elective PCI.

Human Type II Taste Cells Express Angiotensin-Converting Enzyme 2 and Are Infected by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

Chemosensory changes are well-reported symptoms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The virus targets cells for entry by binding of its spike protein to cell-surface angiotensin-converting enzyme 2 (ACE2). It is not known whether ACE2 is expressed on taste receptor cells (TRCs), or whether TRCs are infected directly. in situ hybridization probe and an antibody specific to ACE2 indicated presence of ACE2 on a subpopulation of TRCs (namely, type II cells in taste buds in taste papillae). Fungiform papillae of a SARS-CoV-2+ patient exhibiting symptoms of coronavirus disease 2019 (COVID-19), including taste changes, were biopsied. Presence of replicating SARS-CoV-2 in type II cells was verified by in situ hybridization. Therefore, taste type II cells provide a potential portal for viral entry that predicts vulnerabilities to SARS-CoV-2 in the oral cavity. The continuity and cell turnover of a patient's fungiform papillae taste stem cell layer were disrupted during infection and had not completely recovered 6 weeks after symptom onset. Another patient experiencing post-COVID-19 taste disturbances also had disrupted stem cells. These results demonstrate the possibility that novel and sudden taste changes, frequently reported in COVID-19, may be the result of direct infection of taste papillae by SARS-CoV-2. This may result in impaired taste receptor stem cell activity and suggest that further work is needed to understand the acute and postacute dynamics of viral kinetics in the human taste bud.

Human Taste Cells Express ACE2: a Portal for SARS-CoV-2 Infection.

Loss and changes in taste and smell are well-reported symptoms of SARS-CoV-2 infection. The virus targets cells for entry by high affinity binding of its spike protein to cell-surface angiotensin-converting enzyme- 2 (ACE2). It was not known whether ACE2 is expressed on taste receptor cells (TRCs) nor if TRCs are infected directly. Using an in-situ hybridization (ISH) probe and an antibody specific to ACE2, it seems evident that ACE2 is present on a subpopulation of specialized TRCs, namely, PLCß2 positive, Type II cells in taste buds in taste papillae. Fungiform papillae (FP) of a SARS-CoV-2+ patient exhibiting symptoms of COVID-19, including taste changes, were biopsied. Based on ISH, replicating SARS-CoV-2 was present in Type II cells of this patient. Therefore, taste Type II cells provide a portal for viral entry that predicts vulnerabilities to SARS-CoV-2 in the oral cavity. The continuity and cell turnover of the FP taste stem cell layer of the patient were disrupted during infection and had not fully recovered 6 weeks post symptom onset. Another patient suffering post-COVID-19 taste disturbances also had disrupted stem cells. These results indicate that a COVID-19 patient who experienced taste changes had replicating virus in their taste buds and that SARS-CoV-2 infection results in deficient stem cell turnover needed for differentiation into TRCs.

Effect of Danhong Injection () on Improving Coronary Microcirculation Injury after Percutaneous Coronary Intervention.

OBJECTIVE: To explore the effectiveness of Danhong Injection () on improving microcirculatory injury after percutaneous coronary intervention (PCI) in patients with coronary heart disease (CHD). METHODS: A randomized controlled trial was conducted and 90 patients were enrolled. A random sequence was generated using statistical analysis software. Patients with microcirculatory injuries after PCI were randomly divided into 3 groups for treatment (30 subjects in each group): Danhong Injection group: after PCI, Danghong Injections were given with intravenous administration with 40 mL twice a day for a week; statins intensive group: after PCI, atorvastatin calcium tablets were given oral medication with 80 mg once, and then atorvastatin 40 mg daily for 1 week; the control group: after PCI, atorvastatin calcium tablets were given oral medication with 10-20 mg daily for 1 week. The index of microcirculation resistance (IMR) was used to assess microcirculatory injury during PCI. The IMR of the target vessel was reexamined after 1 week of drug treatment. RESULTS: After one week's drug treatment, IMR was significantly decreased in both statins intensive group and Danhong Injection group compared with the control group (P<0.01), but no difference was found between statins intensive group and Danhong injection group (14.03 ± 2.54 vs. 16.03 ± 5.72 U, P=0.080). CONCLUSIONS: The efficacy of Danhong Injection is non-inferior to statin. Early use of Danhong Injection after PCI can effectively improve coronary microcirculation injury after PCI.

Mitochondrial DNA in extracellular vesicles declines with age.

The mitochondrial free radical theory of aging suggests that accumulating oxidative damage to mitochondria and mitochondrial DNA (mtDNA) plays a central role in aging. Circulating cell-free mtDNA (ccf-mtDNA) isolated from blood may be a biomarker of disease. Extracellular vesicles (EVs) are small (30-400 nm), lipid-bound vesicles capable of shuttling proteins, nucleic acids, and lipids as part of intercellular communication systems. Here, we report that a portion of ccf-mtDNA in plasma is encapsulated in EVs. To address whether EV mtDNA levels change with human age, we analyzed mtDNA in EVs from individuals aged 30-64 years cross-sectionally and longitudinally. EV mtDNA levels decreased with age. Furthermore, the maximal mitochondrial respiration of cultured cells was differentially affected by EVs from old and young donors. Our results suggest that plasma mtDNA is present in EVs, that the level of EV-derived mtDNA is associated with age, and that EVs affect mitochondrial energetics in an EV age-dependent manner.

Anti-Inflammatory and Pro-Autophagy Effects of the Cannabinoid Receptor CB2R: Possibility of Modulation in Type 1 Diabetes.

Type 1 diabetes mellitus (T1DM) is an autoimmune disease resulting from loss of insulin-secreting ß-cells in islets of Langerhans. The loss of ß-cells is initiated when self-tolerance to ß-cell-derived contents breaks down, which leads to T cell-mediated ß-cell damage and, ultimately, ß-cell apoptosis. Many investigations have demonstrated the positive effects of antagonizing cannabinoid receptor 1 (CB1R) in metabolic diseases such as fatty liver disease, obesity, and diabetes mellitus, but the role of cannabinoid receptor 2 (CB2R) in such diseases is relatively unknown. Activation of CB2R is known for its immunosuppressive roles in multiple sclerosis, rheumatoid arthritis, Crohn's, celiac, and lupus diseases, and since autoimmune diseases can share common environmental and genetic factors, we propose CB2R specific agonists may also serve as disease modifiers in diabetes mellitus. The CNR2 gene, which encodes CB2R protein, is the result of a gene duplication of CNR1, which encodes CB1R protein. This ortholog evolved rapidly after transitioning from invertebrates to vertebrate hundreds of million years ago. Human specific CNR2 isoforms are induced by inflammation in pancreatic islets, and a CNR2 nonsynonymous SNP (Q63R) is associated with autoimmune diseases. We collected evidence from the literature and from our own studies demonstrating that CB2R is involved in regulating the inflammasome and especially release of the cytokine interleukin 1B (IL-1ß). Furthermore, CB2R activation controls intracellular autophagy and may regulate secretion of extracellular vesicles from adipocytes that participate in recycling of lipid droplets, dysregulation of which induces chronic inflammation and obesity. CB2R activation may play a similar role in islets of Langerhans. Here, we will discuss future strategies to unravel what roles, if any, CB2R modifiers potentially play in T1DM.

Cell-Type Specific Deletion of CB2 Cannabinoid Receptors in Dopamine Neurons Induced Hyperactivity Phenotype: Possible Relevance to Attention-Deficit Hyperactivity Disorder.

DAT-Cnr2 mice are conditional knockout (cKO) animals that do not express cannabinoid CB2 receptors (CB2R), in midbrain dopamine neurons. The hyperactivity phenotype of DAT-Cnr2 cKO mice were paradoxically reduced by low dose of amphetamine. Here, we report on the locomotor activity analysis in male and female adolescent (PND 30 ± 2) mice in basal conditions and in response to different doses of amphetamine, using the Open Field (OF), Elevated Plus-Maze (EPM) tests and the Novel Object Recognition (NOR) task as a putative model of attention deficit hyperactivity disorder (ADHD). Results showed that both male and female adolescent DAT-Cnr2 mice displayed significant increases in distance traveled in the OF test compared with WT mice. However, 2 mg/kg dose of amphetamine reduced the distance traveled by the DAT-Cnr2 but was increased in the WT mice. In the EPM test of anxiety-like behavioral responses, DAT-Cnr2 spent more time in the open arms of the maze than the WT mice, suggesting a reduction in anxiety-like response. DAT-Cnr2 mice showed significant increase in the number of unprotected head dips in the maze test and in the cliff avoidance reaction (CAR) test demonstrating impulsivity and risky behavior. DAT-Cnr2 mice also exhibited deficient response in the delay decision making (DDM), with impulsive choice. Both DAT-Cnr2 and WT were able to recognize the new object in the NOR task, but the exploration by the DAT-Cnr2 was less than that of the WT mice. Following the administration of 2 mg/kg of amphetamine, the similarities and differential performances of the DAT-Cnr2 and WT mice in the EPM test and NOR task was probably due to increase in attention. Microglia activation detected by Cd11b immunolabelling was enhanced in the hippocampus in DAT-Cnr2 cKO than in WT mice, implicating neuro-immune modulatory effects of CB2R. The results demonstrates that DAT-Cnr2 cKO mice with cell-type specific deletion of CB2R in midbrain dopaminergic neurons may represent a possible model for studying the neurobiological basis of ADHD.