The Power of Wolfram: The weapon to combat type 1 diabetes

I am often asked, "Why do you study such a rare disease, Wolfram?" My answer is, "It is the weapon to combat common diseases." My secret answer is, "I want to help Wolfram patients and their families."

Why it is so important to study Wolfram syndrome, a rare condition characterized by juvenile-onset diabetes, optic atrophy, and neurodegeneration? It is a frightening condition. Wolfram syndrome is always on my mind just like pediatric cancer was always on my mind when I was a young doctor (some people still think that I am a young doctor...thank you). I just want to help them. That's all I want. This is my last research project.

From a scientific standpoint, I always believe that there is a tremendous benefit for us to study Wolfram syndrome. Increasing evidence now indicates that endoplasmic reticulum (ER) dysfunction is involved in more common diseases, especially type 1 diabetes. I propose that Wolfram syndrome is the "weapon to combat type 1 diabetes."

Despite its rarity, Wolfram syndrome probably represents the best model currently available for identifying treatments for diseases associated with ER dysfunction. Wolfram syndrome arises from mutation of a single gene (WFS1), a gene shown to be also involved in β cell dysfunction and death in other forms of diabetes mellitus. Its monogenic etiology makes Wolfram syndrome more amenable to dissecting out the mechanisms underpinning cellular responses to ER dysfunction than other diabetic conditions, such as type 1 diabetes mellitus, in which multiple factors typically interact to produce the disease manifestations.

A common molecular process altered in Wolfram syndrome and type 1 diabetes

We have revealed the mechanisms of cell death in Wolfram syndrome and type 1 diabetes, and our findings will be published in Endocrinology soon. In short, calcium leakage from the endoplasmic reticulum is a common molecular process altered in Wolfram syndrome and type 1 diabetes. We are trying to control this process to develop a novel treatment for Wolfram syndrome. Two more research articles related to this topic are under review.

Endocrinology. 2014. [In press]
Calcium efflux from the endoplasmic reticulum leads to β cell death.
Hara T, Mahadevan J, Kanekura K, Hara M, Lu S, Urano F.
Abstract
It has been established that intracellular calcium homeostasis is critical for survival and function of pancreatic β cells. However, the role of endoplasmic calcium (ER) calcium homeostasis in β cell survival and death is not clear. Here we show that ER calcium depletion plays a critical role in β cell death. Various pathological conditions associated with β cell death, including ER stress, oxidative stress, palmitate, and chronic high glucose, decreased ER calcium levels and SERCA2b expression, leading to β cell death. Ectopic expression of mutant insulin and genetic ablation of WFS1, a causative gene for Wolfram syndrome, also decreased ER calcium levels and induced β cell death. Hyperactivation of calpain-2, a calcium dependent proapoptotic protease, was detected in β cells undergoing ER calcium depletion. Ectopic expression of SERCA2b, as well as pioglitazone and rapamycin treatment, could prevent calcium efflux from the ER and mitigate β cell death under various stress conditions. Our results reveal a critical role of ER calcium depletion in β cell death and indicate that identification of pathways and chemical compounds restoring ER calcium levels will lead to novel therapeutic modalities and pharmacologic interventions for type 1 and type 2 diabetes and other ER-related diseases including Wolfram syndrome.

Patient-based therapeutics part 3

Instead of introducing my research activities,  I would like to introduce my colleagues today. I have a lot of colleagues who have been helping me develop diagnostics and therapeutics for Wolfram at the Washington University Medical Center. Without their help, I cannot accomplish anything. I give many lectures and talks on Wolfram syndrome, but I feel that I am just a spokesperson or a salesman of our team.

Today I would like to introduce Dr. Bess Marshall and Dr. Tamara Hershey. Dr. Marshall is a pediatric endocrinologist and serves as a medical director of our annual Wolfram clinic. Dr. Marshall is an experienced, smart, and caring physician scientist. Dr. Hershey is a neuropsychologist and serves as a scientific director of our Wolfram clinic. Dr. Hershey is thoughtful, smart, and extremely good at getting things done. They are powerful driving force of our Wolfram project! I always appreciate their continuous support and advice. Here is their picture! (From left to right: Dr. Marshall, Fumi, and Dr. Hershey)

Patient-based therapeutics part 2

We are taking an unconventional approach to develop therapeutics for Wolfram syndrome. I would call it "patient-based therapeutics." This implies a few things. One of these is the  "mechanism-based treatment." How can we achieve this component of "patient-based therapeutics" for Wolfram syndrome? Here are our current efforts.

1. Looking for FDA-approved drugs that can potentially halt progression of Wolfram syndrome (drug repurposing).
We looked for drugs that can protect cell death mediated by the leakage of calcium from the endoplasmic reticulum (ER) to the cytosol. We found four FDA approved drugs and one supplement so far. We are testing these drugs in Wolfram iPSC-derived neural progenitor cells and mouse models of Wolfram syndrome.

2. Looking for a new class of drugs that can protect cell death mediated by endoplasmic reticulum dysfunction.
We have developed a drug screening method to identify drugs that can protect cell death mediated by ER dysfunction. In collaboration with a non-profit organization, we are actively looking for a new class of drugs that can potentially halt the progression of Wolfram. 

3. Testing if MANF (mesencephalic astrocyte-derived neurotrophic factor) can suppress the ER calcium leakage-mediated neuronal cell dysfunction in Wolfram iPSC-derived neural progenitor cells.

I will talk about more on MANF some other time. I thought that this was a good biomarker for Wolfram syndrome because expression of this molecule is increased by ER dysfunction. However, the increase of MANF might be an adaptive mechanism of our cells to cope with abnormal ER function.

A novel way to monitor blood sugar levels has been developed. How about electrolyte levels?

It has been announced that Google has invented a novel way to monitor blood glucose levels for patients with diabetes. This is wonderful news. We also need a new device by which we can monitor electrolyte levels in blood easily. Some patients with Wolfram experience low sodium levels. This is probably due to the combined effects of diabetes mellitus, diabetes insipidus, and DDAVP treatment. Low sodium is life-threatening. We need a small device that a patient can carry to monitor blood sodium levels.
http://abcnews.go.com/Health/google-contact-lens-monitor-diabetes-holds-promise/story?id=21577373

What is the link between Wolfram syndrome and type 1 diabetes? Part 1

I often get the following question. "What is the link between Wolfram syndrome and type 1 diabetes?" My answer is "Endoplasmic reticulum dysfunction."

Both Wolfram syndrome and type 1 diabetes are characterized by juvenile-onset diabetes. We need to note that some patients with Wolfram syndrome and type 1 diabetes develop diabetes in adulthood. Both in Wolfram syndrome and type 1 diabetes, beta cells in pancreas that produce insulin are destroyed. In type 1 diabetes, the etiology of beta cell death is autoimmunity. What is autoimmunity?

Our immune system protects us from invading organisms that can cause illness. In healthy states, our immune system does not attack our own cells. In type 1 diabetes, our immune system attacks our own pancreatic beta cells and destroys them. I call this "unintentional suicide." What we don't know is how autoimmunity is induced. Accumulating data in my lab and Dr. Emil Unanue's lab at Washington University suggest that endoplasmic reticulum dysfunction creates "neoantigen" in our beta cells, leading to autoimmunity. Neoantigen means abnormal cell products that can be mistakenly recognized as invading organisms.

Because the root cause of Wolfram syndrome is endoplasmic reticulum dysfunction, it is possible that a novel drug or an intervention for Wolfram syndrome can be beneficial for patients with type 1 diabetes. This is still a theory. The theory does not help patients, the treatment based on the theory does.

Three step formula for developing therapeutics and Three activities to execute it

1. Three-Step Formula For Developing Therapeutics for Wolfram syndrome

Here is my three-step formula for developing therapeutics for Wolfram syndrome.

Step 1. Understand the disease

Step 2. Identify drug targets and biomarkers

Step 3. Develop drugs and treat patients

To execute these three steps, we have three ongoing activities at the Washington University Medical Center.

2. Three Activities at Washington University Medical Center

2-1. Wolfram syndrome International Patient Registry

We are collecting the medical records, blood samples, and genetic information from patients with Wolfram syndrome through the internet. (Step 1).

2-2. Wolfram syndrome Clinic

We host a Wolfram syndrome clinic every year to understand the natural history of the disease. Many physicians and staff members have been involved in this activity. It is important to understand the major clinical problems and the progression of the disease (Step 1). It is also important to determine the baseline conditions of each patient for a future clinical trial.

2-3. Patient-based therapeutic development

We are taking an unconventional approach to develop therapeutics for Wolfram syndrome. I would call it "patient-based therapeutics." I discussed this concept yesterday.

MANF, Wolfram, and Diabetes: What is MANF?

Since a biotech company in California licensed my invention on MANF for therapeutics and diagnostics for Wolfram syndrome and Type 1 diabetes, I have been getting a lot of emails on this topic. I would like to briefly explain you about MANF. In short, MANF is one of our targets for developing patient-based therapeutics and diagnostics for Wolfram syndrome and type 1 diabetes.

MANF stands for mesencephalic astrocyte-derived neurotrophic factor. This molecule is created in our body, and it was originally isolated from a type of brain cells called astrocytes. Several years ago, we discovered that MANF was secreted from pancreatic beta cells and neurons when their endoplasmic reticulum calcium was depleted. We thought that this was a potential biomarker for Wolfram syndrome and filed an invention disclosure. Interestingly, we found several articles reporting that MANF can confer protection against neuronal cell death mediated by endoplasmic reticulum dysfunction. So we started testing if MANF might confer protection against pancreatic beta cell death mediated by ER dysfunction, and the preliminary results were positive.

We still have to do a lot of preclinical studies. Also, the company that has licensed our invention is mainly developing drugs for Parkinson's disease. However, it is good news that they are also interested in Wolfram syndrome and type 1 diabetes.

My last conversation with my father on January 15th, 1988

My father passed away 26 years ago on January 15th. He had a terminal cancer, and my brother and I were still in our teens. It was devastating to our family. At his death bed, I promised him that I would be a doctor and make a difference in the future of patients. My father was a physician scientist, and professor and chair at the University of Tokyo, the best university in Japan. He was a doctor for the Japanese Emperor's family. He was a hematologist and studying leukemia in children. I was always proud of him and believed that he would get a Nobel Prize in Medicine. I have just talked with my brother and mother who are both physicians, and remembered why I decided to become a doctor and study diseases in children. I alway feel that my father is still watching me and helping me.

Patient-based therapeutics part 1

We are taking an unconventional approach to develop therapeutics for Wolfram syndrome. I would call it "patient-based therapeutics." Our extensive molecular characterization of patient cells, especially iPSC-derived cells, has been providing us remarkable insights into the root cause of Wolfram syndrome. Based on these insights, I have been carefully choosing molecular targets and processes for developing therapeutics. These are the endoplasmic reticulum (ER) membrane integrity, ER calcium leakage, calpain-2, and WFS1 gene mutations. 

How we target WFS1 gene mutations? We have started testing genome editing to accomplish this. Genome editing is a process that involves cutting out pathogenic genetic material (i.e., mutations in the WFS1 gene) and replacing it with healthy genetic material. This is a molecular surgery. So I am becoming a molecular surgeon. In short, we are trying to repair a genetic defect in Wolfram syndrome. 

Currently, we are repairing a genetic defect in iPS cells from patients with Wolfram syndrome to see if the molecular surgery can restore the normal function of neural progenitor cells derived from Wolfram iPS cells. This is an important step. When the transplantation of iPSC-derived retinal ganglion cells and beta cells are available in the clinic in the future, we need to repair the genetic defect before the transplantation.

Strategy for developing drugs for the treatment of Wolfram syndrome - my current efforts

I have two goals for treating patients with Wolfram syndrome.

1. Halt the progression by drugs.

2. Restore damaged tissues using iPSCs cells modified by the genome editing.

As I mentioned before, we created iPSCs (induced pluripotent stem cells) using skin cells from patients with Wolfram syndrome. These cells can be differentiated into any types of cells.

I'd like to briefly summarize my efforts on goal #1 today. To discover drugs, I am currently leading three projects.

1. Looking for FDA-approved drugs that can potentially halt progression of Wolfram syndrome.

We looked for drugs that can protect cell death mediated by the leakage of calcium from the endoplasmic reticulum (ER) to the cytosol. We found four FDA approved drugs and one supplement so far. We are testing these drugs in Wolfram iPSC-derived neural progenitor cells and mouse models of Wolfram syndrome.

2. Looking for a new class of drugs that can protect cell death mediated by endoplasmic reticulum dysfunction.

We have developed a drug screening method to identify drugs that can protect cell death mediated by ER dysfunction. In collaboration with a non-profit organization, we are actively looking for a new class of drugs that can potentially halt the progression of Wolfram. 

3. Testing if MANF (mesencephalic astrocyte-derived neurotrophic factor) can suppress the ER calcium leakage-mediated neuronal cell dysfunction in Wolfram iPSC-derived neural progenitor cells.

I will talk about more on MANF some other time. I thought that this was a good biomarker for Wolfram syndrome because expression of this molecule is increased by ER dysfunction. However, the increase of MANF might be an adaptive mechanisms of our cells to cope with abnormal ER function.

Treating vision impairment part 2 - my concept

We are actively working on induced pluripotent stem cells (iPSCs) to replace damaged tissues in patients with Wolfram syndrome and type 1 diabetes in the future. iPSCs are a type of stem cells derived from skin cells through forced expression of specific genes. In short, we can create any type of cells from skin cells of each patient through iPSCs.

We have created iPSCs using skin cells from patients with Wolfram syndrome here at Washington University. These cells can be differentiated into any types of cells including retinal ganglion cells and pancreatic beta cells that are severely damaged in Wolfram syndrome. We have already created neural progenitor cells from iPSCs. Our next step is to make retinal ganglion cells from iPSCs-derived neural progenitor cells. Our future goal is to correct genetic defects in iPSCs, make iPSC-derived retinal ganglion cells, and transplant these cells to patients.

This strategy will be used for treating age-related macular degeneration, a leading cause of vision loss among people age 50 and older, and the first clinical trial will start in March, 2014 in Japan. I sincerely hope that this trial will be successful. The information about this trial is summarized in Nature.

http://blogs.nature.com/news/2013/07/japan-to-start-stem-cell-study-on-humans.html

Treating vision impairment part 1 - my concept

One of the most frequent questions that I get from patients with Wolfram syndrome and type 1 diabetes is how we can treat blindness. I have one answer right now.

The mechanisms of vision impairment in Wolfram syndrome and type 1 diabetes are different. In short, the vision impairment in type 1 diabetes is a problem in small blood vessels supplying nutrition to the eyes. It is caused by high blood sugar levels and called retinopathy. The vision impairment in Wolfram syndrome is a problem in neuronal cells in the eyes transferring the electrical signal produced in the eye to the brain. It is caused by neuronal cell death and called optic atrophy.

Today, I will focus on optic atrophy. One of the major neuronal cells in the eyes declining in Wolfram syndrome are "retinal ganglion cells" which transmit electrical signals to the brain. If we can make these cells and transplant them to Wolfram patients, we can possibly treat blindness or improve eyesight. To accomplish this, we need a source for new retinal ganglion cells. I believe that induced pluripotent stem cells (iPSCs) is the source for the new retinal ganglion cells. I will explain you about the iPSC cells in my next blog.

What is Diabetes Insipidus?

Diabetes insipidus is one of the common symptoms in patients with Wolfram syndrome. It is defined as the passage of large volumes of dilute urine. It has the 2 major forms, and patients with Wolfram have the central diabetes insipidus.

1. Central (neurogenic, pituitary, or neurohypophyseal): characterized by decreased secretion of antidiuretic hormone called vasopressin.

2. Nephrogenic: characterized by decreased ability to concentrate urine because of resistance to vasopressin action in the kidney.

A potential target for the treatment of Wolfram syndrome

Since I moved to Washington University School of Medicine in July, 2012, the pace of my research on Wolfram syndrome has accelerated. I have a much better understanding of the disorder clinically and at the molecular level. As I mentioned in my blog a year ago, I believe that calcium leakage from the endoplasmic reticulum to the cytosol is one of the major etiologies for beta cell death and neurodegeneration in Wolfram. We have discovered that the calcium leakage results in calpain-2 enzyme activation and cell death. These findings will be published very soon. We are looking for drugs that can prevent this process. If my theory holds true, the drug that can halt the calcium leakage should delay the progression of the disease.

My goal in 2014, a small scale interventional study for Wolfram syndrome

My goal this year is to start a small scale interventional study for Wolfram syndrome. I believe that conducting a clinical trial in a small group of patients with Wolfram syndrome of homogeneous etiology could potentially lead to a breakthrough in treatments for other conditions associated with endoplasmic reticulum dysfunction, including type 1 diabetes and neurodegeneration. We all should be aware and appreciate the power of rare diseases, such as Wolfram syndrome. I was recently asked to write my view on type 1 diabetes and Wolfram syndrome by Nature, and this was just published. I hope... sincerely hope that this article will raise awareness of Wolfram syndrome. 
http://www.nature.com/nrendo/journal/vaop/ncurrent/full/nrendo.2013.261.html