Iron Oxide Nanoparticle-Incorporated Mesenchymal Stem Cells for Alzheimer's Disease Treatment.

Alzheimer's disease (AD) is a neurodegenerative disease with multifactorial pathogenesis. However, most current therapeutic approaches for AD target a single pathophysiological mechanism, generally resulting in unsatisfactory therapeutic outcomes. Recently, mesenchymal stem cell (MSC) therapy, which targets multiple pathological mechanisms of AD, has been explored as a novel treatment. However, the low brain retention efficiency of administered MSCs limits their therapeutic efficacy. In addition, autologous MSCs from AD patients may have poor therapeutic abilities. Here, we overcome these limitations by developing iron oxide nanoparticle (IONP)-incorporated human Wharton's jelly-derived MSCs (MSC-IONPs). IONPs promote therapeutic molecule expression in MSCs. Following intracerebroventricular injection, MSC-IONPs showed a higher brain retention efficiency under magnetic guidance. This potentiates the therapeutic efficacy of MSCs in murine models of AD. Furthermore, human Wharton's jelly-derived allogeneic MSCs may exhibit higher therapeutic abilities than those of autologous MSCs in aged AD patients. This strategy may pave the way for developing MSC therapies for AD.

A New Method of Myostatin Inhibition in Mice via Oral Administration of Lactobacillus casei Expressing Modified Myostatin Protein, BLS-M22.

Myostatin is a member of the transforming growth factor-beta superfamily and is an endogenous negative regulator of muscle growth. This study aimed to determine whether an oral administration of Lactobacillus casei expressing modified human myostatin (BLS-M22) could elicit sufficient levels of myostatin-specific antibody and improve the dystrophic features of an animal model of Duchenne muscular dystrophy (DMD; mdx mouse). BLS-M22 is a recombinant L. casei engineered to harbor the pKV vector and poly-gamma-glutamic acid gene linked to a modified human myostatin gene. Serological analysis showed that anti-myostatin IgG titers were significantly increased, and serum creatine kinase was significantly reduced in the BLS-M22-treated mdx mice compared to the control mice. In addition, treatment of BLS-M22 resulted in a significant increase in body weight and motor function (Rotarod behavior test). Histological analysis showed an improvement in the dystrophic features (fibrosis and muscle hypertrophy) of the mdx mice with the administration of BLS-M22. The circulating antibodies generated after BLS-M22 oral administration successfully lowered serum myostatin concentration. Myostatin blockade resulted in serological, histological, and functional improvements in mdx mice. Overall, the findings suggest the potential of BLS-M22 to treat DMD; however, further clinical trials are essential to ascertain its efficacy and safety in humans.

Intracerebroventricular Administration of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Induces Transient Inflammation in a Transgenic Mouse Model and Patients with Alzheimer's Disease.

Previously we conducted a Phase I/IIa clinical trial in nine patients with mild to moderate Alzheimer's disease (AD). Unexpectedly, all patients who were given injections of human-umbilical cord-blood-derived mesenchymal stem cells (hUCB-MSCs) developed fever which subsided after 24 h. Several possible causes of transient fever include bacterial infection, inflammatory reaction from the cell culture media composition, or the cells themselves. To delineate these causes, first we compared the levels of several cytokines in the cerebrospinal fluid (CSF) of AD patients who received saline (placebo) or hUCB-MSC injections, respectively. Compared to the placebo group, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and c-reactive protein (CRP) levels were increased in the hUCB-MSC group. Negative bacterial culture results of the CSF samples and the fact that the same hUCB-MSC administration procedure was used for both the placebo and hUCB-MSC groups ruled out the bacterial infection hypothesis. However, it was not yet clear as to whether the transplanted cells or the composition of the cell culture media generated the transient fever. Therefore, we carried out intracerebroventricular (ICV) injections of hUCB-MSCs in a 5xFAD mouse model of AD. Interestingly, we discovered that pro-inflammatory cytokine levels were higher in the hUCB-MSC group. Taken together, our data suggest that the cause of transient inflammatory response observed from both the clinical trial and mouse study was due to the transplanted hUCB-MSCs.

Recent trends in opioid prescriptions in Korea from 2002 to 2015 based on the Korean NHIS-NSC cohort.

OBJECTIVES: Opioids are prescribed to treat moderate to severe pain. We investigated recent trends in opioid (morphine, oxycodone, fentanyl, and hydromorphone) prescriptions using data from the Korean National Health Insurance Service-National Sample Cohort between 2002 and 2015. METHODS: The morphine milligram equivalent (MME) was calculated to standardize the relative potency of opioids. The number (cases) or amount (MME) of annual opioid prescriptions per 10,000 registrants was computed to analyze trends in opioid prescriptions after age standardization. Joinpoint regression analysis was conducted to calculate the annual percentage change and average annual percentage change (AAPC). RESULTS: The number (cases) of prescriptions per 10,000 registrants increased from 0.07 in 2002 to 41.23 in 2015 (AAPC, 76.0%; 95% confidence interval [CI], 61.6 to 91.7). The MME per 10,000 registrants increased from 15.06 in 2002 to 40,727.80 in 2015 (AAPC, 103.0%; 95% CI, 78.2 to 131.3). The highest AAPC of prescriptions and MME per 10,000 registrants were observed in the elderly (60-69 years) and in patients treated at general hospitals. Fentanyl prescriptions increased most rapidly among the 4 opioids. CONCLUSIONS: Consumption of opioids greatly increased in Korea over the 14-year study period.

Wharton's Jelly-Derived Mesenchymal Stem Cells Reduce Fibrosis in a Mouse Model of Duchenne Muscular Dystrophy by Upregulating microRNA 499.

The aim of this study was to evaluate the therapeutic effects and mechanisms of Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) in an animal model of Duchenne muscular dystrophy (DMD). Mdx mice (3-5 months old) were administered five different doses of WJ-MSCs through their tail veins. A week after injection, grip strength measurements, creatine kinase (CK) assays, immunohistochemistry, and western blots were performed for comparison between healthy mice, mdx control mice, and WJ-MSC-injected mdx mice. WJ-MSCs exerted dose-dependent multisystem therapeutic effects in mdx mice, by decreasing CK, recovering normal behavior, regenerating muscle, and reducing apoptosis and fibrosis in skeletal muscle. We also confirmed that miR-499-5p is significantly downregulated in mdx mice, and that intravenous injection of WJ-MSCs enhanced its expression, leading to anti-fibrotic effects via targeting TGFßR 1 and 3. Thus, WJ-MSCs may represent novel allogeneic "off-the-shelf" cellular products for the treatment of DMD and possibly other muscle disorders.

Immunosuppressant Drugs Mitigate Immune Responses Generated by Human Mesenchymal Stem Cells Transplanted into the Mouse Parenchyma.

It has been widely accepted that mesenchymal stem cells (MSCs) can evade the immune surveillance of the recipient. However, emerging research cast doubt on whether MSCs are intrinsically immune-privileged. Previously, we observed that the transplantation of human MSCs (hMSCs) into the mouse parenchyma attracted a high infiltration of leukocytes into the injection tract. Thus, in order to reduce the immune responses generated by hMSCs, the aim of this study was to assess which immunosuppressant condition (dexamethasone only, tacrolimus only, or dexamethasone and tacrolimus together) would not only reduce the overall immune response but also enhance the persistence of MSCs engrafted into the caudate putamen of wild-type C57BL/6 mice. According to immunohistochemical analysis, compared to the hMSC only group, the administration of immunosuppressants (for all three conditions) reduced the infiltration of CD45-positive leukocytes and neutrophils at the site of injection. The highest hMSC persistence was detected from the group that received combinatorial administrations of dexamethasone and tacrolimus. Moreover, compared to the immunocompetent WT mouse, higher MSC engraftment was observed from the immunodeficient BALB/c mice. The results of this study support the use of immunosuppressants to tackle MSC-mediated immune responses and to possibly prolong the engraftment of transplanted MSCs.

Metformin use in cancer survivors with diabetes reduces all-cause mortality, based on the Korean National Health Insurance Service between 2002 and 2015.

ABSTRACT: Malignant neoplasms are the leading cause of death in Korea. We aimed to examine if metformin use in cancer survivors reduces all-cause mortality. This study was retrospectively designed based on data from the Korean National Health Insurance Service-National Health Screening Cohort (HEALS) between 2002 and 2015. The Kaplan-Meier estimator and log-rank test was performed to estimate the survival function according to metformin usage (3721 metformin non-users with diabetes, 5580 metformin users with diabetes, and 24,483 non-diabetic individuals). Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated using Cox proportional hazards regression models.The median follow-up duration was 4.2 years. The HRs (95% CIs) for all-cause mortality of metformin users and the non-diabetic group were 0.762 (0.683-0.850) and 1.055 (0.966-1.152) in men and 0.805 (0.649-0.999), and 1.049 (0.873-1.260) in women, respectively, compared with metformin non-users among diabetic cancer survivors, in a fully adjusted model. After stratifying metformin users into pre- and post-diagnosis of cancers, adjusted HRs (95% CIs) of pre- and post-diagnosis metformin users for all-cause mortality were 0.948 (0.839-1.071) and 0.530 (0.452-0.621) in men and 1.163 (0.921-1.469) and 0.439 (0.323-0.596) in women, respectively.Metformin use in cancer survivors with diabetes reduced overall mortality rates. In particular, metformin use after cancer diagnosis, not before cancer diagnosis, was inversely associated with overall mortality.Active treatment with metformin for diabetic cancer survivors after cancer diagnosis can improve their survival rates.

Comparing different types of statins for secondary prevention of cardio-cerebrovascular disease from a national cohort study.

Statins have been recommended for use in atherosclerotic cardio-cerebrovascular disease (CCVD). The purpose of this study was to investigate the efficacy of five different types of statin in the secondary prevention of CCVD in patients. This study retrospectively designed and analyzed data from the National Health Insurance Service-National Health in Korea. Participants aged 40 to 69 years were categorized into five statin groups (atorvastatin, rosuvastatin, pitavastatin, simvastatin, and pravastatin). The primary composite outcome was defined as recurrence of CCVD or all causes of death. Cox proportional hazard regression models were adopted after stepwise adjustments for confounders to investigate the difference in efficacy among the different statins. Of the 755 final participants, 48 patients experienced primary composite outcomes. After adjustments, the hazard ratios (95% confidence intervals) for primary composite outcomes of atorvastatin, pitavastatin, and rosuvastatin groups were 0.956 (0.456-2.005), 1.347 (0.354-5.116), and 0.943 (0.317-2.803), respectively, when compared with the simvastatin group. There were no significant differences between the statins in efficacy for preventing recurrence of CCVD events and/or death in CCVD patients.

Intraspinal Cavity Injection of Human Mesenchymal Stem Cells and Tracking their Migration into the Rat Brain.

Mesenchymal stem cells (MSCs) have been studied for the treatment of various diseases. In neurodegenerative diseases involving defects in both the brain and the spinal cord, the route of administration is very important, because MSCs must migrate to both the brain and the spinal cord. This paper describes a method for administering MSCs into the spinal canal (intraspinal cavity injection) that can target the brain and spinal cord in a rat model. One million MSCs were injected into the spinal canals of rats at the level of lumbar vertebrae 2-3. After administration, the rats were euthanized at 0, 6, and 12 h post-injection. Optical imaging and quantitative real-time polymerase chain reaction (qPCR) were used to track the injected MSCs. The results of the present study demonstrated that MSCs administered via the spinal cavity could be detected subsequently in both the brain and spinal cord at 12 h. Intraspinal cavity injection has the advantage of not requiring general anesthesia and has few side effects. However, the drawback of the low migration rate of MSCs to the brain must be overcome.

Radio-Frequency Vector Magnetic Field Mapping in Magnetic Resonance Imaging.

A method is presented to measure the radio-frequency (RF) vector magnetic field inside an object using magnetic resonance imaging (MRI). Conventional " [Formula: see text] mapping" in MRI can measure the proton co-rotating component ( [Formula: see text] of the RF field produced by a transmit coil. Here we show that by repeating [Formula: see text] mapping on the same object and coil at multiple (8) specific orientations with respect to the main magnet, the magnitudes and relative phases of all (x, y, z) Cartesian components of the RF field can be determined unambiguously. We demonstrate the method on a circularly polarized volume coil and a loop coil tuned at 123.25 MHz in a 3 Tesla MRI scanner, with liquid phantoms. The volume coil measurement showed the axial component of the RF field, which is normally unmeasurable in MRI, away from the center of the coil. The measured RF vector field maps of both coils compared favorably with numerical simulation, with volumetric normalized root-mean-square difference in the range of 7~20%. While the proposed method cannot be applied to human imaging at present, applications to phantoms and small animals could provide a useful experimental tool to validate RF simulation and verify certain assumptions in [Formula: see text] map-based electrical properties tomography (EPT).

Metformin usage and the risk of colorectal cancer: a national cohort study.

PURPOSE: This study aimed to investigate the association between metformin usage and the risk of colorectal cancer (CRC) using data from the Korean National Health Insurance Service-National Health Screening Cohort database. METHODS: Data from the NHIS-HEALS cohort between 2002 and 2015 were longitudinally analyzed. Subjects were divided into three groups: metformin non-users with diabetes mellitus (DM), metformin users with DM, and no DM group. CRC was defined using the ICD-10 code (C18.0-C20.0) at the time of admission. Cox proportional hazard regression models were adopted after stepwise adjustment for confounders to investigate the association between metformin usage and colorectal cancer risk. RESULTS: During the follow-up period, of the total 323,430 participants, 2341 (1.33%) of the 175,495 males and 1204 (0.81%) of the 147,935 females were newly diagnosed with CRC. The estimated cumulative incidence of CRC was significantly different among the three groups based on Kaplan-Meier's survival curve (p values < 0.05 in both sexes). Compared with metformin non-users, hazard ratios (95% CIs) of metformin users and the no DM group were 0.66 (0.51-0.85) and 0.72 (0.61-0.85) in males and 0.59 (0.37-0.92) and 0.93 (0.66-1.29) in females, respectively, after being fully adjusted. CONCLUSIONS: Metformin users with diabetes appear to have a significantly lower risk of CRC compared with metformin non-users.

Metformin use in elderly population with diabetes reduced the risk of dementia in a dose-dependent manner, based on the Korean NHIS-HEALS cohort.

AIMS: The aim of this study is to investigate the association between metformin usage and dementia in an elderly Korean population. METHODS: Participants were divided into five groups: metformin non-users with diabetes mellitus (DM), metformin users with DM (low-, mid-, and high-users), and non-diabetic Individuals. Dementia was defined with primary diagnostic dementia codes according to the 10th edition of the International Classification of Diseases. To compare the incidence rate of dementia among the five groups, Kaplan-Meier estimates and log-rank test were employed. Also, to control the confounding factors, Cox proportional hazards regression models were fitted in a sequential adjustment. RESULTS: The median follow-up was 12.4 years. The overall incidence rate of dementia was 11.3% (8.4% in men and 13.9% in women). Compared with metformin non-users, hazard ratios (95% confidence intervals) of low-, mid-, and high-users and non-diabetic individuals for dementia were 0.97 (0.73-1.28), 0.77 (0.58-1.01), 0.48 (0.35-0.67), and 0.98 (0.84-1.15), respectively, in men, respectively, and 0.90 (0.65-0.98), 0.61 (0.50-0.76), 0.46 (0.36-0.58), and 0.92 (0.81-1.04), respectively, in women, after full adjustment of confounding variables. CONCLUSIONS: Metformin use in an elderly population with DM reduced dementia risk in a dose-response manner.

Primary Prevention of Cardiocerebrovascular Diseases and Related Deaths According to Statin Type.

(1) Background: Statin is the mainstay of treatment for the primary prevention of atherosclerotic cardiocerebrovascular diseases (CCVDs) in adults with hypercholesterolemia. This study aims to investigate the differences in effect on primary composite outcomes (CCVDs and CCVD-related deaths) among five statins in hypercholesterolemic individuals. (2) Methods: This retrospective study is based on the Korean National Health Insurance Service-National Health Screening Cohort. Participants, aged 40 to 69 years at baseline, were categorized into five statin-treated groups (pitavastatin, atorvastatin, rosuvastatin, simvastatin, and pravastatin) and two untreated groups (untreated hypercholesterolemia and no hypercholesterolemia). (3) Results: A total of 161,583 individuals was included. The median follow-up period was 8.2 years. Compared with the pitavastatin group, the hazard ratios (HRs; 95% confidence intervals (CIs)) for CCVDs and CCVD-related deaths of the atorvastatin, rosuvastatin, simvastatin, pravastatin, untreated hypercholesterolemia, and no-hypercholesterolemia groups were 0.969 (0.567-1.657), 0.988 (0.533-1.832), 0.862 (0.490-1.518), 0.906 (0.326-2.515), 2.665 (1.556-4.562), and 0.656 (0.388-1.110), respectively, in men and 1.124 (0.632-1.999), 1.119 (0.582-2.152), 1.324 (0.730-2.400), 1.023 (0.330-3.171), 2.650 (1.476-4.758), and 0.921 (0.522-1.625), respectively, in women, after being fully adjusted. (4) Conclusions: No significant differences among the five statins were observed, but there was an increased risk in untreated hypercholesterolemic individuals, for CCVDs and CCVDs-related deaths in individuals with hypercholesterolemia of either sex.

Pressure Stimuli Improve the Proliferation of Wharton's Jelly-Derived Mesenchymal Stem Cells under Hypoxic Culture Conditions.

Mesenchymal stem cells (MSCs) are safe, and they have good therapeutic efficacy through their paracrine action. However, long-term culture to produce sufficient MSCs for clinical use can result in side-effects, such as an inevitable senescence and the reduction of the therapeutic efficacy of the MSCs. In order to overcome this, the primary culture conditions of the MSCs can be modified to simulate the stem cells' niche environment, resulting in accelerated proliferation, the achievement of the target production yield at earlier passages, and the improvement of the therapeutic efficacy. We exposed Wharton's jelly-derived MSCs (WJ-MSCs) to pressure stimuli during the primary culture step. In order to evaluate the proliferation, stemness, and therapeutic efficacy of WJ-MSCs, image, genetic, and Western blot analyses were carried out. Compared with standard incubation culture conditions, the cell proliferation was significantly improved when the WJ-MSCs were exposed to pressure stimuli. However, the therapeutic efficacy (the promotion of cell proliferation and anti-apoptotic effects) and the stemness of the WJ-MSCs was maintained, regardless of the culture conditions. Exposure to pressure stimuli is a simple and efficient way to improve WJ-MSC proliferation without causing changes in stemness and therapeutic efficacy. In this way, clinical-grade WJ-MSCs can be produced rapidly and used for therapeutic applications.

Exploring the Potential of Mesenchymal Stem Cell-Based Therapy in Mouse Models of Vascular Cognitive Impairment.

Closely linked to Alzheimer's disease (AD), the pathological spectrum of vascular cognitive impairment (VCI) is known to be wide and complex. Considering that multiple instead of a single targeting approach is considered a treatment option for such complicated diseases, the multifaceted aspects of mesenchymal stem cells (MSCs) make them a suitable candidate to tackle the heterogeneity of VCI. MSCs were delivered via the intracerebroventricular (ICV) route in mice that were subjected to VCI by carotid artery stenosis. VCI was induced in C57BL6/J mice wild type (C57VCI) mice by applying a combination of ameroid constrictors and microcoils, while ameroid constrictors alone were bilaterally applied to 5xFAD (transgenic AD mouse model) mice (5xVCI). Compared to the controls (minimal essential medium (MEM)-injected C57VCI mice), changes in spatial working memory were not noted in the MSC-injected C57VCI mice, and unexpectedly, the mortality rate was higher. In contrast, compared to the MEM-injected 5xVCI mice, mortality was not observed, and the spatial working memory was also improved in MSC-injected 5xVCI mice. Disease progression of the VCI-induced mice seems to be affected by the method of carotid artery stenosis and due to this heterogeneity, various factors must be considered to maximize the therapeutic benefits exerted by MSCs. Factors, such as the optimal MSC injection time point, cell concentration, sacrifice time point, and immunogenicity of the transplanted cells, must all be adequately addressed so that MSCs can be appropriately and effectively used as a treatment option for VCI.

Metformin use reduced the overall risk of cancer in diabetic patients: A study based on the Korean NHIS-HEALS cohort.

BACKGROUND AND AIM: Several studies have reported the preventive effect of metformin on cancer development. This study aimed to investigate the relationship between use of metformin and risk of cancer in Koreans. METHODS AND RESULTS: This study was designed retrospectively using the National Health Insurance Service-National Health Screening Cohort conducted between 2002 and 2015. 40 to 69-year-old subjects who received a health screening examination from 2002 to 2003 were enrolled. Hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer were estimated in a multivariate Cox proportional regression analysis. A total of 323,430 subjects was enrolled (301,905 individuals without diabetes [No DM], 8643 diabetic patients with metformin treatment [metformin users], and 12,882 diabetic patients without metformin treatment [metformin non-users]). The median follow-up period was 12.7 years. Cumulative incidence of overall cancer was 7.9% (7.7, 10.3, and 11.1% in No DM, metformin users and non-users, respectively). Compared to metformin non-users, the fully adjusted HRs (95% CIs) of metformin users and No DM for overall cancer incidence were 0.73 (0.66-0.81) and 0.75 (0.64-0.88), respectively, in men and 0.83 (0.78-0.89) and 0.81 (0.72-0.92) in women. CONCLUSIONS: Diabetic patients receiving metformin treatment, and individuals without diabetes were at lower risk for cancer incidence than diabetic patients without metformin treatment.

Intrathecal Injection in A Rat Model: A Potential Route to Deliver Human Wharton's Jelly-Derived Mesenchymal Stem Cells into the Brain.

Mesenchymal stem cells (MSCs) are considered as promising therapeutic agents for neurodegenerative disorders because they can reduce underlying pathology and also repair damaged tissues. Regarding the delivery of MSCs into the brain, intravenous and intra-arterial routes may be less feasible than intraparenchymal and intracerebroventricular routes due to the blood-brain barrier. Compared to the intraparenchymal or intracerebroventricular routes, however, the intrathecal route may have advantages: this route can deliver MSCs throughout the entire neuraxis and it is less invasive since brain surgery is not required. The objective of this study was to investigate the distribution of human Wharton's jelly-derived MSCs (WJ-MSCs) injected via the intrathecal route in a rat model. WJ-MSCs (1 × 106) were intrathecally injected via the L2-3 intervertebral space in 6-week-old Sprague Dawley rats. These rats were then sacrificed at varying time points: 0, 6, and 12 h following injection. At 12 h, a significant number of MSCs were detected in the brain but not in other organs. Furthermore, with a 10-fold higher dose of WJ-MSCs, there was a substantial increase in the number of cells migrating to the brain. These results suggest that the intrathecal route can be a promising route for the performance of stem cell therapy for CNS diseases.

Development of New Preventive and Therapeutic Vaccines for Tuberculosis.

Tuberculosis (TB) is a contagious disease that has been responsible for the death of one billion people in the last 200 years. Until now, the only vaccine approved for the prevention of TB is Bacillus Calmette-Guérin (BCG), which is prepared by attenuating Mycobacterium bovis. However, one of the limitations of BCG is that its preventive effect against pulmonary TB varies from person to person. Therefore, there arises a need for a new TB vaccine to replace or supplement BCG. In this review, we have summarized the findings of current clinical trials on preventive and therapeutic TB vaccine candidates. In addition, we have discussed a novel vaccination approach using the cell-based vaccine presenting early secretory antigenic target-6 (ESAT-6), which is a potent immunogenic antigen. The role of ESAT-6 in hosts has also been described.