The Bioinformatics CRO Podcast

Transcript of Episode 34: Saroja Voruganti

Disclaimer: Transcripts may contain errors.

Grace Ratley: [00:00:00] Welcome to The Bioinformatics CRO Podcast. My name is Grace Ratley, and today I’m joined by Dr. Saroja Voruganti. Saroja is Associate Professor of Nutrition at the University of North Carolina at Chapel Hill and her lab studies Nutrigenomics and Nutrigenetics. Welcome, Saroja.

Saroja Voruganti: [00:00:17] Thank you, Grace. I’m happy to be here.

Grace Ratley: [00:00:19] We’re happy to have you. So can you give us a little bit of a description about what your lab does?

Saroja Voruganti: [00:00:25] Yeah. As you mentioned, we do study Nutrigenomics and Nutrigenetics. We are trying to understand how genes affect, how our nutrients are metabolized, how they are broken up in the body, and how genes affect that process, which is termed as nutrigenetics. The other side we have how nutrients affect how the genes are expressed, which is the nutrigenomics part. So we are trying to understand how these nutrients and genes interact in relation to subsequent disease risk. So my labs interest mainly is purine metabolic pathway. So we are trying to understand how the enzymes work or how genes affect those enzymes, how the nutrients affect this pathway and how it subsequently affects various diseases, mainly studying neurodegenerative diseases as well as obesity, how it affects those.

Grace Ratley: [00:01:23] Awesome. So can you give us a little bit of an idea of how what we eat changes purine metabolism?

Saroja Voruganti: [00:01:29] So a key example I can give you is fructose, in normal levels is fine. The problem comes up when you have too much and then not many people know, but it releases a molecule which can further convert into uric acid, which is a purine and uric acid again, in normal levels is an antioxidant. It’s good for your body, which is an end product of purine metabolism. But I’m talking about all this when it is too much like you don’t realize you drink, you eat fructose containing drinks and food and we don’t realize how much we are taking it in. And it causes more production of uric acid, which if it is too much in the body, it can turn into a pro-oxidant and cause harmful effects. So fructose is only one of them though. But you have other products like any purines, alcohol. Everything in moderation is okay. When I talk about these foods, I’m talking about when it is too much. So that’s why we always insist on moderation and balance in your foods, right.

Grace Ratley: [00:02:36] Yeah. And notoriously high fructose corn syrup is in high concentration in sodas and such. And for our listeners, purines are things like adenine and guanine. So the nucleotides that build our DNA and our RNA.

Saroja Voruganti: [00:02:50] Exactly. Yeah. And most of the organ meats and all contain hyperons. But if you see purines themselves only contribute 10% to the total purine content. The other products like fructose and all also contribute quite a bit.

Grace Ratley: [00:03:05] Why did you get into Nutrigenomics?

Saroja Voruganti: [00:03:08] I’ve always done nutrition. Back in India, I had done my bachelor’s in foods and nutrition, which is called, and then I did a dietetics course there. Then I moved to US for my husband’s job and after several years of gap, I started thinking of going back to school and the only thing I knew was nutrition. So we were in Austin at that time. I went to UT Austin. I thought, I’ll do Masters, but eventually it became a PhD, So I did my nutritional sciences. I’m in PhD in nutritional sciences. We did a study there where we were trying to give an ideal diet to some women and I saw that they were all similar age groups, similar weight. All were women. So sex wise, they were all same.

Still there was so much difference in how they responded. And I started getting interested into genetics, like how genetics plays a role. So I started looking at various ethnic groups as well as within ethnic groups. Also how genetic variation can affect, how people respond to diet. One of my committee members was Dr. [Comuzzi], who is an expert in genetics of obesity. When I finished my PhD, I went to him and said, I would like to do a postdoctoral fellowship with you and understand more about genetics. And he was nice enough. Without any genetics background, he agreed to let me do his postdoc fellowship with him. So that was when I started getting interested. Like how are genes affect, how nutrients are metabolized or how are nutrients affect the way genes are expressed.

Grace Ratley: [00:04:46] Yeah, I find that very exciting. I know that within nutrition research, it’s very common for people to say something is good for you or bad for you, but there’s a lot of variation within the population.

Saroja Voruganti: [00:04:59] Yeah. Based on a person’s gender and race ethnicity. And there are so many other factors. We haven’t even touched the tip of the iceberg.

Grace Ratley: [00:05:10] Yeah, it’s a very complicated field. So you study nutritional science, but your initial degree was in dietetics. Can you give us a little bit of a difference between that?

Saroja Voruganti: [00:05:21] See, that’s what happened right. When I was doing my dietetics, I did study the biology behind it, how the metabolism happens and how you give a diet plan to people. But there’s so many complexities involved in it, like the genetics or now we know a lot about microbiome and there are so many other things involved. Unless you have a very deep understanding, I feel like it’s difficult to convince people to change their diet or even one nutrient. In dietetics, we do understand metabolism and all, but I didn’t feel that it was comprehensive. I think Dietetics plus nutritional Sciences is a very good combination, but I don’t know how many people can do both.

Grace Ratley: [00:06:03] What do you think is needed for us to move nutritional science into applications and into something that people can actually act upon in their day to day lives?

Saroja Voruganti: [00:06:15] I think as we are closing in to this precision nutrition, can we precisely say who needs how much food? We’re working towards it, but we are not there yet, of course, because we need to understand all the genetic variation. Also, we have been only studying single nucleotide polymorphisms in detail, but there is so much other genetic variation, structural variation which we haven’t even touched in detail, like copy number variation and many others. And then we haven’t even looked at gene expression. So that’s what our lab also does. We initially looked at individual nutrients, how they affect gene expression. Now we are looking at combinations like fructose plus caffeine, fructose plus salt, and then we plan to do like a meal. And then we need to understand how are we going to translate that to a layperson. If I tell a person that, Oh, you have this copy number variants, you need to eat this, the person may not understand anything. So if you are able to convince them that, you have this susceptibility and maybe if you start early to eat properly or do physical activity, you may either delay the onset of a certain disease or may completely prevent it. Why even go for treatments if you can prevent it? Basically, I think the way we part the information, that becomes very important.

Grace Ratley: [00:07:42] Yeah. And so how do you think people are going to get access to this information? Do you think this information will come from screening when people are children or from kits like 23andMe or something along those lines?

Saroja Voruganti: [00:07:56] I like the system of Iceland where they sequence every person, which is okay for a small country, but not for United States. So it may be very difficult, but maybe do something like that. Actually, I would like it to be like when you go to a doctor, they take a blood sample and send it to a lab for lipids or something, lipid panel or something. Similarly, if they can draw blood and send it to a lab or some genetic lab and they can immediately have a set of genotypes which they can do it in a day or two, genotype them and send back their data. And they say, Oh, you have this certain genetic variants, so maybe you should follow this, this, this or something like that. That would be ideal. We are working towards it and I’m quite optimistic that we will be there soon. I don’t know when, but soon. The problem is that we ourselves don’t know what is the role of a lot of genetic variants. So I think first we need to dive deeper into it, understand it, and then come up with a consensus set of like, let’s say these genetic variants are associated with dyslipidemia or these are with diabetes mellitus or something like that. Now we have also complexity with microbiome and other factors, so it’s not easy, but at least if we can take care of 40% of it or 50% of it, it helps.

Grace Ratley: [00:09:24] Definitely. That’s one of the reasons why I really enjoy learning about nutrition. It’s that complexity and figuring out how much of what we look like or how healthy we are can we attribute to our lifestyle or our genetics or our microbiome. I feel nutrition gets a bad rep because it’s so hard to study, it’s so complex. And I feel every study has different criteria and it’s really difficult to look across them and see the same result every time.

Saroja Voruganti: [00:09:56] Yeah, I agree. And also another thing which adds to complexity is we really don’t have good ways of measuring the diet. So all we are doing is food frequency questionnaires and dietary calls, which is so much focused on memory. I don’t remember what I ate yesterday half the time, so I have to think so much. Even if I remember, how much did I eat?

Grace Ratley: [00:10:23] It takes a long time. I’ve used the OneFit app or something like that. Yousit down and it takes 15 to 20 minutes to log everything that you ate. Like I ate five almonds.

Saroja Voruganti: [00:10:35] It’s not easy. So when we do studies, I feel bad for the participants because it’s not easy. I wish we can find something more objective. So a lot of people depend on metabolomics. Metabolomics is a good surrogate, but we need something more.

Grace Ratley: [00:10:52] Yeah. And for our listeners, can you give us a little bit about what metabolomics is?

Saroja Voruganti: [00:10:56] Metabolomics is study of the final breakdown products of metabolism. So like proteins, amino acids will be your metabolites for carbohydrates. You have monosaccharides like fructose glucose, and then for fats they will be fatty acids, different types of fatty acids. But remember that these have all been metabolized and what we have in the blood is what we find. So there will be so much variation in it. But if some person’s diet is steady over a period, maybe metabolomics is actually a good measure till we find something better for dietary intake. For now, they’re very good markers because we don’t have anything else. So we should use that in combination of what you have collected from dietary intake recalls and food frequency questionnaire.

Grace Ratley: [00:11:50] What other scientific tools have been really key to this growth of the field of Nutrigenomics and Nutrigenetics?

Saroja Voruganti: [00:11:58] Mainly sequencing is pretty much within our reach. Earlier it was very expensive and all. Sequencing is getting very cheap so soon I think whole genome sequencing will be very cost effective. I think that is a major thing. And then now we can sequence microbiome. So that is also very interesting. And then metabolomics is getting very cheap. So you can do untargeted metabolomics. If you want to understand general metabolomics, it’s like whole genome sequencing. You do every metabolite measure, every metabolite and see or if you are only interested in a pathway like myself, we go for targeted and look at what is happening in that field. Yeah, but we do need some other like enzyme chemistry, HPLCs or all to add to it. Yeah, I think we are in a much better position now with a lot of nutrition related ones and genetics.

Grace Ratley: [00:12:58] What sort of simplified advice could you give to someone who is looking to improve their health.

Saroja Voruganti: [00:13:03] Based on genetics, I don’t know whether we can advise. So right now I will just say like we always say, do moderation. Don’t stop anything completely, especially macronutrients. Don’t stop completely carbohydrates or fats or protein. The other thing is, of course, portion control, which we always been telling. Even if there’s so much on the plate, try not to eat the whole thing. Try to control your portion for now. A lot of people have shown that Mediterranean diet is actually very good for cardiovascular health. And you have DASH diets, you have specific diets and all. You don’t have to do major changes like in one of your ingredients, you can reduce it. Like salt a little bit less or oil a little bit less, so slowly. And still make a difference. So why not? We are just trying to see how we can keep healthy people healthy, not after they have got hypertension. And we are telling that, oh, follow DASH diet. It’s good for them to follow that diet anyway.

Grace Ratley: [00:14:11] Yeah. And I feel like a lot of people get their health information from doctors who are always on the other end. People go to the doctor when they have something wrong and not so much for prevention.

Saroja Voruganti: [00:14:24] Exactly. And doctors also realizing the importance of nutrition now. And they also refer quite a few people to dietitians. But I agree with you that this is after something has happened. Not everybody, but at least people who are genetically susceptible to certain diseases, maybe they can start early exercising more or eat in a better way or something like that so that they can at least delay and improve their quality of life.

Grace Ratley: [00:14:54] I like this idea of potentially using nutrition as a medicine, as a therapeutic or as a preventative thing.

Saroja Voruganti: [00:15:01] Yeah. And actually, I’m at Nutrition Research Institute. We are big on using food as medicine or food as preventive medicine or something like that. So if we can do it with food, why go for treatment?

Grace Ratley: [00:15:15] Right. For some reason, it’s very difficult to convince people that investing in your health early or investing time and effort into nutrition early can really save so much money and trouble down the line. Why do you think that is?

Saroja Voruganti: [00:15:33] There’s something like my son used to say when he was really small that why is healthy food always so non good tasting or why is tasty food always not healthy? Like if we deep fry something, they are very tasty all the time. If the same thing is baked, it is good, but it’s not the same level. So I think how we present it, how it tastes, smells, it makes a lot of difference on what people eat. That is why Dr. Ammerman, she does something called culinary medicine. Those biscuits are there, Bojangles biscuits. She made like those type of biscuits, but with healthy oils and all. So I really like what she does. It’s she’s trying to present similar food but in a healthier version. So if people take to that, if it smell, taste and everything is good, then I think people will accept it. It’s just that they want to enjoy food. Food is something which is a topic for meetings and parties, culturally festivals. Everybody wants to be healthy. Who doesn’t want to be healthy, but they will also want to enjoy food. I think, yeah, culinary medicine has an important role to play.

[00:16:51] And secondly, I think the time for preparation. We did a study when I was doing my PhD several years ago, that was supposed to be a weight loss study and the mothers ended up. They were all low income mothers. Most of them ended up gaining weight. We were trying to teach them all nice exercises and nice recipes and all, but one lady told me that we work three jobs a day. I have to run from one job to another. Where do I have time to do your exercises or prepare the food? I just pick up something from McDonald’s and take it home. I need to get something for my children. So we have to have foods which taste similar and they have to be affordable to people and should not take too long to prepare because a lot of people don’t have time to prepare them. Once they are not well or once they get some disease, they have no choice. They have to do it. I wish they can do in the earlier part, but nobody will give you a time off because I’m healthy, I want to take some time off. It’ll be counted as vacation or they’ll not give you time off. If I say I’m not well, I want to take one day off. People say, okay, take off a sick leave, but I say I’m healthy, but I still want to take one day off. People will frown on that person. Why they want to take off. It’s my thing that we should also invest in healthy people too, so that they stay healthy.

Grace Ratley: [00:18:16] Perhaps even more so investing in healthy people.

Saroja Voruganti: [00:18:19] Yeah. I know that we have to treat people who are not well. I agree totally. But we also have to invest in healthy people because we don’t want them to move to the dark side or something like that. So yeah, I think we need to do a lot more work, but I’m so excited to be in this field because this is something we can make a difference like you’re born with certain genes, you can’t do anything about it. But how they’re expressed is in our hands and what we eat, like lifestyle factors are in our hands.

Grace Ratley: [00:18:52] Exactly. And I think you brought up an interesting point with the low income women gaining weight and people who are in lower incomes tend to be at higher risk for a lot of these diseases and for having poor diets. And it gets into this accessibility aspect. Do you think that Nutrigenomics will be accessible to people who are in lower income areas or who are diverse in ethnicity or race?

Saroja Voruganti: [00:19:19] Initially, genetic databases were not really representative of various groups, but now there are a lot of groups, especially consortiums, which are trying to get more the genetic databases updated with ethnically different populations. So most of the studies have been done in Caucasians because the study started in Europe and US. So that is how it happened. But now we are trying to push more representation from African-Americans, Asians and Hispanics. So yeah, there is a push, but it will take some time for accessibility. First, we need wide representation in genetic databases. Secondly, we need wide representation in studies so that we know more about each population. I’m studying about a genetically isolated, homogeneous population, which hardly people know about them and they are very hesitant to participate in these type of studies. So we need more representation. I’m originally from Asia, I’m from India originally, but all Asians are clubbed together, but there is so much diversity within Asians. Similarly, Latin Americans. What does that mean? There is so much genetic diversity. Even within Africa, there is so much genetic variation. So we need representation from everybody. So once we have that, then our genetic databases will be very rich and diverse. I know we want to do a personalized nutrition someday, but at least right now our focus is a genetically susceptible group. So if we can divide it into groups or ethnic level, that will be an intermediate step before we actually go to the personalized nutrition.

Grace Ratley: [00:21:01] So how did you get interested in nutrition?

Saroja Voruganti: [00:21:05] Initially, my interest was all biochemistry, and then I had a subject called Food Science, and I took that and I was very interested in how you can prepare different foods, different types of foods. And each food has the way you prepare it, it can taste different. My first experiment, how you whisk that. So if you use different whisks, you’ll get a different types of foams. It was like simplest one and I was so fascinated and I started looking into deeper into it like what is involved in an egg? And then slowly, slowly I got interested in nutrition and nutrition is, after all, biochemistry. Biochemistry and nutrition are so closely linked. So that’s how I got interested in nutrition. And then I said, Oh, this is so cool. And I went into dietetics. But soon I realized that I can’t advise people unless I know more about this subject. What other thing I realized that foods are culturally so deep rooted in communities. It’s so difficult for us to ask them to change. So I thought, okay, why not go get in deeper into it and understand more so when we moved to us, I did not want to pursue dietetics. I wanted to go into research because I wanted to understand more about each nutrient combination of nutrients. And so that’s how I moved to nutrition. But they are all so closely interrelated. So it is you can say nutritional biochemistry that was what I was interested in.

Grace Ratley: [00:22:40] Yeah, that’s what I always tell people. I majored in because then I get less questions about French fries and things.

Saroja Voruganti: [00:22:47] Yeah. So nutritional biochemistry and then I got into nutritional genetics you can say that. And then when the group which I was working with postdoctoral fellow, they were working with several groups like Dr. Comuzzi, like we had datasets from Hispanics, Arabs like Omanis, Arabs, Alaskan natives and American Indians. So I was like, I had so much opportunity to look at each ethnicity and really, really got interested into minority research and diversity research and all. So I have tried to continue that work at NRI or UNC.

Grace Ratley: [00:23:25] It’s very important work and I’m glad that there are people like you out there studying these things and helping not just the average white American, but the average American and the average person in the world. It’s not just an America.

Saroja Voruganti: [00:23:40] Yeah. Anybody like white or anybody. We need to keep healthy people healthy and see that they don’t progress to something. And those who have already progressed have a disease or something, keep them there and not make them progress to become worse or something.

Grace Ratley: [00:24:00] Yeah. Do you do a lot of cooking at home?

Saroja Voruganti: [00:24:03] Uh, I used to. Nowadays I don’t have much time, but I do. And I use very little oil. When my husband prepares the food much, much more tasty because he uses traditional. But my foods are not that tasty. So I keep telling him. And then I saw how much oil he uses. I’m like, okay, I’m not watching when you’re cooking. I can’t.

Grace Ratley: [00:24:29] Yeah, but it’s just not to know how much is in there.

Saroja Voruganti: [00:24:32] Yeah, yeah, yeah, yeah. But that’s why I was telling you, right, that we need to start thinking of how we can prepare the same type of food with less oil, which is I don’t know how, but we have done so much research. We have done so many discoveries, I’m sure we can find something.

Grace Ratley: [00:24:49] Right. I always come back to that. Yes, I know what’s good for me, but I also know what’s really tasty. It’s so hard.

Saroja Voruganti: [00:24:59] Yeah, it is hard.

Grace Ratley: [00:25:00] So last question to young scientists or scientists who are interested in exploring the topic of nutrition, what advice would you give to these people?

Saroja Voruganti: [00:25:12] I’m very passionate about nutrition, so I would encourage people to come in. And also it may apply to any field actually. Don’t expect overnight results. This will resist research. Of course, it will take some time. But what is interesting is that you can make a difference. You can figure out changes and all. So I think I would love to have more people working in nutrition. There’s so much complexity in this field. Just don’t think that it is all about cooking or anything. So just remember that we are like engineers and then doctors are more like mechanics. So someone told me this like I was explaining to them this pathway. And also they told me that, Oh, you are like an engineer, and doctor is like mechanical. So yeah, get deeper into it. And really you have to enjoy the field to be working in this, make this field your own and just deep into it and enjoy. Because not only that there is a lot of complexity and a lot of scope, but this is a field where you can make a difference sooner than later, actually compared to other fields. And luckily most of them do not have side effects if taken in moderation. Nutrition in that way is.

Grace Ratley: [00:26:34] It’s like high benefit, low cost.

Saroja Voruganti: [00:26:36] Exactly. Yeah. And some things I’m very quite excited about the way different ethnic groups have cultures, their own cultural foods, and they all have some scientific significance, even though maybe their ancestors know or do not know about science, we don’t know. But the combinations of a tortilla and beans. There is a variation in India too, and everywhere there is certain variation of that. It makes so much difference because together they have essential all essential amino acids. So at that time, I don’t know if they knew science or not, but that’s an ideal combination, tortilla, wheat flour plus beans. I’m really fascinated by looking at their cultural foods and how well they have all the essential amino acids and they make such a good combination. There’s so much more to learn in nutrition, not just a biochemistry. Biochemistry is part of it, but culturally, socially, psychologically. There’s so many aspects of nutrition. There’s so much to learn. So I encourage the students to come and choose whatever aspect they want to choose. They can choose a social aspect or cultural or genetic aspects, which I’m doing or microbiome aspect. So there is like so much to learn and so much more to investigate. This is like a gold mine.

Grace Ratley: [00:28:03] I agree. Well, thank you so much for coming on our podcast, Saroja. You have a wonderful perspective and so much knowledge and passion about nutrition, and I hope that our listeners can take some of that away with them.

Saroja Voruganti: [00:28:15] It’s my pleasure. It was very nice talking to you.